fix: improvements

- Added @radix-ui/react-toggle and @radix-ui/react-toggle-group to package dependencies.
- Implemented ToggleGroup and Toggle components for improved UI interaction.
- Replaced custom toast notifications with Sonner for better user feedback.
- Updated CanvasPage and ProjectsPage to utilize new toast notifications.
- Removed obsolete toast context and provider.
- Enhanced ProjectsPage with a toggle view for project display (cards/table).

.dockerignore

@@ -0,0 +1,24 @@
+# Monorepo: each service builds from its own context (frontend/, backend/).
+# This file applies to root-level builds only.
+node_modules
+**/node_modules
+dist
+**/dist
+.git
+.gitignore
+*.md
+.env*
+.env.*
+!.env.example
+.idea
+.vscode
+*.log
+.DS_Store
+Thumbs.db
+**/__tests__
+**/*.test.ts
+**/*.test.tsx
+**/*.spec.ts
+**/*.spec.tsx
+coverage
+.nyc_output

.gitignore

@@ -1,5 +1,6 @@
 # dependencies
-/node_modules
+node_modules
+
 /.pnp
 .pnp.js
 
@@ -9,14 +10,15 @@
 # production build
 /build
 /dist
+frontend/dist
+
+# environment (keep .env.example if you add one)
+.env
+.env.*
+!.env.example
 
 # misc
 .DS_Store
-.env
-.env.local
-.env.development.local
-.env.test.local
-.env.production.local
 
 # logs
 npm-debug.log*
@@ -38,3 +40,7 @@ Thumbs.db
 .cache
 .parcel-cache
 
+# Docker (optional local overrides)
+docker-compose.override.yml
+docker-compose.override.yaml
+

.vite/deps/_metadata.json

@@ -0,0 +1,8 @@
+{
+  "hash": "dba24d0a",
+  "configHash": "beca0bba",
+  "lockfileHash": "85459ac0",
+  "browserHash": "3fd5087e",
+  "optimized": {},
+  "chunks": {}
+}

.vite/deps/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

ARCHITECTURE.md

@@ -0,0 +1,216 @@
+# Architecture Overview
+
+## 1. Executive Summary
+
+Zui is a node-based visual editor for composing configs, templates, variables, and AI-generated content. The frontend is a React 18 SPA backed by a thin Express API for AI agent calls. All graph data is persisted in `localStorage`; the backend is stateless.
+
+---
+
+## 2. Technology Stack
+
+| Layer | Technology |
+| --- | --- |
+| Frontend framework | React 18, TypeScript (strict), Vite 7 |
+| Graph canvas | `@xyflow/react` v12 (React Flow) |
+| State management | Zustand 5 (command/reducer pattern) |
+| Styling | Tailwind CSS + Shadcn UI (`@radix-ui/*`) |
+| Rich text | BlockNote 0.36 with custom blocks |
+| Templating | Nunjucks |
+| Graph traversal | `graphology` + `graphology-traversal` |
+| Routing | React Router v6 |
+| Backend | Node.js 20+, TypeScript, Express 4 |
+| AI SDK | Vercel AI SDK v4 + `@ai-sdk/openai` |
+| Testing | Vitest, React Testing Library |
+
+---
+
+## 3. Project Structure
+
+```text
+frontend/src/
+├── main.tsx                    # Entry: registers node types & config types, mounts app
+├── app/
+│   ├── canvas/                 # CanvasPage, canvasStore (Zustand), canvasStore.test.ts
+│   ├── kosmos/                 # KosmosPage, sidebar, AI settings, KosmosContext
+│   └── recollections/
+│       ├── RecollectionsPage   # Workspace list
+│       ├── RecollectionLayout  # Shared layout (sidebar + outlet)
+│       ├── flux/               # Flux view (graph canvas)
+│       ├── logos/              # Logos view (BlockNote rich text)
+│       └── katalogos/          # Katalogos view (artifact gallery)
+├── components/
+│   ├── graph/                  # AnimatedEdge, BaseNode, handles, keyboard shortcuts
+│   ├── nodes/                  # One folder per node type
+│   └── ui/                     # Shadcn primitives
+├── hooks/                      # useGraphStateWithHistory, useResizeHeight, …
+└── lib/
+    └── graph/
+        ├── nodeRegistry.ts     # Mutable plugin registry
+        ├── registerBuiltinNodes.tsx
+        ├── nodeTypeBuilder.ts  # Fluent builder for node descriptors
+        ├── configTypes.ts      # Output type registry (plantuml, markdown, wireframe)
+        ├── rendering.ts        # 3-step rendering pipeline contract
+        ├── state.ts            # Graph state types
+        └── canvasStore/        # Reducer + selectors
+
+backend/src/
+├── index.ts                    # Express app, CORS, routes, error handler
+├── routes/agentRoutes.ts       # POST /api/agent, POST /api/agent/stream
+├── services/agentService.ts    # LLM call logic (Vercel AI SDK)
+├── repositories/cacheRepository.ts
+├── models/index.ts
+└── middleware/rateLimiter.ts
+```
+
+---
+
+## 4. Key Architectural Patterns
+
+### 4.1 Command / Reducer Store (canvasStore)
+
+The Zustand canvas store uses a pure reducer (`canvasStoreReducer`) with a discriminated union of `CanvasCommand` types. All mutations go through `dispatch(command)`. In dev mode every command is logged to the console.
+
+The store has three slices:
+
+- **`graph`** — nodes and edges (the React Flow state)
+- **`path`** — trigger pulse for edge animation
+- **`ui`** — renaming state, fullscreen node, pending connection
+
+### 4.2 Delta-based Undo / Redo
+
+`useGraphStateWithHistory` computes *inverse deltas* (only the nodes/edges that changed) rather than snapshotting the full graph. Maximum 100 history entries. Drag operations commit a pre-drag snapshot on `onNodeDragStop`.
+
+### 4.3 Node Plugin Registry
+
+Node types are registered via a mutable registry in `nodeRegistry.ts`. The built-ins are registered at app init from `registerBuiltinNodes.tsx`. Adding a new node type requires:
+
+1. Implement a React component for the node.
+2. Create a descriptor using `NodeTypeBuilder`.
+3. Call `registerNodeType(descriptor)` — no edits to core code.
+
+### 4.4 Fluent Builder for Node Descriptors
+
+`NodeTypeBuilder` provides a type-safe method-chaining API (`idPrefix`, `withInputOutput`, `classification`, `allowedSourceTypes`, `help`, `menu`, `withFullscreen`, `sourceRenderingLogic`, …). Required fields are validated at `.build()`.
+
+### 4.5 Three-Step Rendering Pipeline
+
+Defined as an explicit contract in `rendering.ts`:
+
+1. **Resolve** — source node (Config/Agent) produces `{ resolved, outputTypeId, reasoning? }`
+2. **Render** — output type handler converts the resolved string (PlantUML → Kroki SVG, Markdown → HTML, Wireframe → SVG)
+3. **Display** — the Rendering node shows an image viewport or scrollable HTML
+
+### 4.6 Node Classification System
+
+Four metaphorical classes drive the create menu grouping:
+
+| Class | Node type | Metaphor |
+| --- | --- | --- |
+| `psyche` | Variable | source / input |
+| `physis` | Data (CSV) | physical data |
+| `pneuma` | Config / Render | transformation |
+| `archon` | Agent | AI / LLM |
+
+### 4.7 Recollections (Workspaces)
+
+Each workspace (recollection) is stored in `localStorage`:
+
+| Key | Content |
+| --- | --- |
+| `zui_platform_recollections` | Metadata index (id, name, icon, timestamps) |
+| `zui_graph_<id>` | Flux graph (nodes + edges) |
+| `zui_logos_<id>` | BlockNote rich text document |
+| `zui_render_cache_<id>` | Rendered artifact cache |
+
+Legacy key prefix `emanations` is migrated to `recollections` on first load.
+
+### 4.8 User-configurable AI Connection
+
+`KosmosContext` persists `aiConnection` (provider, baseURL, model, apiKey) in `localStorage` under `zui_ai_connection`. The Agent node forwards this to the backend with each request, so users can switch between OpenAI and local LLMs (LM Studio, Ollama) from the UI without env variable changes.
+
+### 4.9 Diagram Rendering via Kroki
+
+PlantUML diagrams are rendered by proxying to `https://kroki.io` via `/api/kroki/plantuml/svg`. This proxy is configured in both the Vite dev server and Nginx production config. Timeout: 15 seconds.
+
+---
+
+## 5. Data Flow
+
+```text
+User interaction
+  → dispatch(CanvasCommand)              [canvasStore reducer]
+  → Zustand state update                 [graph / path / ui slices]
+  → React re-render                      [React Flow nodes/edges]
+
+Rendering node triggered
+  → Resolve source node                  [Config/Agent → resolved string]
+  → Render output type                   [plantuml/markdown/wireframe]
+    → Kroki proxy  (PlantUML)            [GET /api/kroki/plantuml/svg]
+    → Agent backend  (AI)               [POST /api/agent or /api/agent/stream]
+  → Display artifact                     [image / HTML / SVG viewport]
+
+Agent node (streaming)
+  → POST /api/agent/stream               [Express → agentService]
+  → Vercel AI SDK streams SSE            [backend → frontend]
+  → useStreamingContent hook consumes    [updates node data]
+```
+
+---
+
+## 6. Backend Architecture
+
+The backend is intentionally thin and stateless. It has three responsibilities:
+
+1. **Proxy AI calls** — forwards prompts to the configured LLM (OpenAI or OpenAI-compatible).
+2. **Stream responses** — `POST /api/agent/stream` uses `pipeTextStreamToResponse` from the Vercel AI SDK.
+3. **Health check** — `GET /health` for Docker/orchestration readiness probes.
+
+The `InMemoryCache` and `rateLimiter` middleware are implemented but not yet wired into the agent routes.
+
+---
+
+## 7. Contribution Workflow
+
+1. Fork the repository and clone locally.
+2. Install dependencies: `cd frontend && npm install` and `cd backend && npm install`.
+3. Run the dev servers (see README).
+4. Create a feature branch: `git checkout -b feat/your-feature`.
+5. Follow the Coding Standards (see [CONTRIBUTING.md](CONTRIBUTING.md)).
+6. Submit a Pull Request with a descriptive title, linked issue(s), updated tests, and documentation changes if relevant.
+
+### PR Review Checklist
+
+- [ ] Readability: clear naming, minimal nesting
+- [ ] TypeScript: no `any`, strict types throughout
+- [ ] Performance: no unnecessary re-renders, proper memoization
+- [ ] Accessibility: semantic HTML, ARIA attributes where needed
+- [ ] Security: no hardcoded secrets, input validated at boundaries
+
+---
+
+## 8. Coding Standards
+
+- **TypeScript**: strict mode (`strict`, `noImplicitAny`, `noUnusedLocals`).
+- **Naming**: PascalCase for components, camelCase for functions/variables, UPPER_SNAKE_CASE for constants.
+- **File structure**: domain-grouped under `src/app/<domain>/` and `src/components/<category>/`.
+- **Formatting**: Prettier via `frontend/prettier.config.cjs`; line length ≤ 120.
+- **Comments**: JSDoc for public APIs; inline only where logic is non-obvious.
+
+---
+
+## 9. Quick Reference for AI Agents
+
+| Topic | Location |
+| --- | --- |
+| Entry point | `frontend/src/main.tsx` |
+| Canvas store | `frontend/src/app/canvas/canvasStore.ts` |
+| Store reducer | `frontend/src/app/canvas/canvasStoreReducer.ts` |
+| Node registry | `frontend/src/lib/graph/nodeRegistry.ts` |
+| Node builder | `frontend/src/lib/graph/nodeTypeBuilder.ts` |
+| Rendering pipeline | `frontend/src/lib/graph/rendering.ts` |
+| Built-in node registration | `frontend/src/lib/graph/registerBuiltinNodes.tsx` |
+| AI settings context | `frontend/src/app/kosmos/KosmosContext.tsx` |
+| Backend entry | `backend/src/index.ts` |
+| Agent service | `backend/src/services/agentService.ts` |
+
+*This document is a living reference; update it when architectural decisions change.*

CONTRIBUTING.md

@@ -0,0 +1,61 @@
+# Contribution Guide
+
+## 1. Coding Standards
+
+- Use TypeScript with `strict` mode enabled; no `any` types.
+- Import order: core libs → third-party → project aliases (`@/`) → relative.
+- Naming: PascalCase for components, camelCase for functions/variables, UPPER_SNAKE_CASE for constants.
+- Add JSDoc comments for all public APIs and exported types.
+- Line length ≤ 120 characters; use Prettier for formatting (`frontend/prettier.config.cjs`).
+- Run `npm run lint` and fix all warnings before opening a PR.
+
+## 2. Branch Workflow
+
+- Create a feature branch: `git checkout -b feat/<short-description>`
+- Keep branches up to date with `main` via `git rebase`.
+- Submit a Pull Request with a clear title and description.
+- Ensure the PR passes CI (tests, lint, type-check).
+- Address review comments promptly.
+
+## 3. Running Tests
+
+```bash
+# Install dependencies
+cd frontend && npm install
+
+# Run tests in watch mode
+npm run test
+
+# Run tests once (CI)
+npm run test:run
+
+# Type-check
+npx tsc --noEmit
+```
+
+## 4. Making Your First Contribution
+
+1. Pick a beginner-friendly issue labeled `good first issue`.
+2. Read [ARCHITECTURE.md](ARCHITECTURE.md) to understand the relevant module.
+3. Make a small, focused change; avoid refactoring unrelated code.
+4. Run the relevant tests and confirm they pass.
+5. Commit and push, then open a PR with a clear description of what and why.
+
+## 5. Where to Extend
+
+| Goal | Where to look |
+| --- | --- |
+| Add a new node type | `src/lib/graph/nodeTypeBuilder.ts` + `registerBuiltinNodes.tsx` |
+| Add a new output/render type | `src/lib/graph/configTypes.ts` + `rendering.ts` |
+| Change canvas state shape | `src/app/canvas/canvasStore.ts` + reducer + tests |
+| Add a new Logos block | `src/app/recollections/logos/logosSchema.ts` |
+| Add a backend endpoint | `backend/src/routes/` → `services/` → `index.ts` |
+
+## 6. Useful Links
+
+- [ARCHITECTURE.md](ARCHITECTURE.md) — architecture overview, key patterns, module map
+- [PERFORMANCE_IMPROVEMENTS.md](PERFORMANCE_IMPROVEMENTS.md) — bottleneck analysis and improvement plan
+- [docs/CODE_REVIEW_CHECKLIST.md](docs/CODE_REVIEW_CHECKLIST.md) — PR review checklist
+- [docs/NODE_TYPE_EXTENSIBILITY_PROPOSAL.md](docs/NODE_TYPE_EXTENSIBILITY_PROPOSAL.md) — node plugin system design
+
+*Thank you for contributing!*

PERFORMANCE_IMPROVEMENTS.md

@@ -0,0 +1,108 @@
+# Performance Improvements Plan
+
+## 1. Current State
+
+The core rendering and state management architecture is already well-structured for performance:
+
+- **Command/reducer store** — all mutations go through a pure reducer; individual selectors can prevent unnecessary re-renders.
+- **Delta-based undo/redo** — only diffs are stored, not full graph snapshots (max 100 entries).
+- **Plugin node registry** — node types are loaded once at app init, not dynamically on each render.
+- **Streaming AI responses** — `POST /api/agent/stream` uses SSE so the UI updates incrementally.
+
+The sections below identify remaining bottlenecks and concrete next steps.
+
+---
+
+## 2. Known Bottlenecks
+
+| # | Issue | Location | Impact | Root Cause |
+| --- | --- | --- | --- | --- |
+| 1 | Unguarded re-renders on canvas | `CanvasPage.tsx` | Frame drops on large graphs | Components not subscribed to granular store slices |
+| 2 | Nunjucks template resolution on every render | `rendering.ts` resolve step | Slow Config node updates | No memoization of template output keyed to input hash |
+| 3 | Kroki SVG requests not deduplicated | `rendering.ts` render step | Redundant network calls | No in-flight request deduplication or client-side cache |
+| 4 | Sidebar tree renders all items | `KosmosPage` recollection tree | Scrolling lag with many workspaces | No list virtualization |
+| 5 | Backend cache not wired to agent routes | `agentRoutes.ts` | Repeated identical LLM calls | `InMemoryCache` and `rateLimiter` exist but are unused |
+| 6 | Full graph serialized to localStorage on every change | `useGraphStateWithHistory` | Storage I/O on every keypress | No debounce on the persistence write |
+| 7 | Initial bundle size | Vite build | Slow first load | Heavy deps (BlockNote, React Flow, Nunjucks) loaded eagerly |
+
+---
+
+## 3. Recommended Improvements
+
+### 3.1 Granular Store Subscriptions
+
+Zustand supports slice-level subscriptions. Node components should select only their own data slice:
+
+```ts
+// Instead of subscribing to the entire graph:
+const node = useCanvasStore(s => s.graph.nodes.find(n => n.id === id))
+```
+
+This prevents all nodes from re-rendering when a single node changes.
+
+### 3.2 Memoize Template Resolution
+
+Cache the Nunjucks resolution output keyed to a hash of the template source plus variable inputs. Invalidate only when those inputs change:
+
+```ts
+const resolved = useMemo(
+  () => resolveTemplate(template, variables),
+  [templateHash, variableHash]
+)
+```
+
+### 3.3 Deduplicate Kroki Requests
+
+Add a simple in-flight map in the render step: if a request for the same PlantUML source is already pending, reuse its promise. Cache successful responses keyed to the source string with a short TTL (e.g. 5 minutes).
+
+### 3.4 Wire Backend Cache and Rate Limiter
+
+`InMemoryCache` and `rateLimiter` middleware are implemented in `backend/src/`. Connect them to `agentRoutes.ts`:
+
+1. Add cache lookup before calling the AI service.
+2. Store the response on cache miss.
+3. Apply rate limiting per IP to prevent abuse.
+
+### 3.5 Debounce localStorage Writes
+
+Wrap the graph persistence call in a debounce (e.g., 300 ms) to avoid a write on every keystroke or node drag. The delta-based history already computes minimal diffs; the bottleneck is the frequency of writes.
+
+### 3.6 Virtualize the Sidebar Tree
+
+Integrate `react-arborist` (already installed) with virtualization enabled for the recollection sidebar when item count exceeds a threshold (~50).
+
+### 3.7 Code Split Heavy Routes
+
+Add lazy imports for the three heavy route components so the initial bundle only loads what the user navigates to:
+
+```ts
+const FluxRoute    = lazy(() => import('./app/recollections/flux/FluxRoute'))
+const LogosPage    = lazy(() => import('./app/recollections/logos/LogosPage'))
+const KatalogosPage = lazy(() => import('./app/recollections/katalogos/KatalogosPage'))
+```
+
+### 3.8 Enable Brotli Compression in Nginx
+
+Add brotli/gzip compression to `frontend/nginx.conf` for JS, CSS, and SVG assets. This can cut transfer size by 60–70% for the JS bundle.
+
+---
+
+## 4. Success Metrics
+
+| Metric | Current (estimated) | Target |
+| --- | --- | --- |
+| Frame time on 50-node canvas | ~16 ms | < 10 ms |
+| Initial JS bundle (gzipped) | ~800 KB | < 600 KB |
+| Repeated identical LLM calls | uncached | 0 network round-trips |
+| localStorage write frequency | every change | debounced 300 ms |
+
+---
+
+## 5. Contribution Path
+
+1. Read [ARCHITECTURE.md](ARCHITECTURE.md) to understand the module you're optimizing.
+2. Pick one item from section 2.
+3. Add a Vitest benchmark (`performance.now()` before/after) alongside your change.
+4. Submit a PR with the benchmark results in the description and update this file's "Current" column.
+
+*This plan is a living document; update the metrics table when improvements land.*

README.md

@@ -0,0 +1,153 @@
+# Zui
+
+Node-based visual editor (React Flow) for composing configs, variables, templates, and AI-generated content. Three views per workspace: **Flux** (graph canvas), **Logos** (rich text), and **Katalogos** (artifact gallery). Optional Node.js backend for AI agent calls.
+
+## Project layout
+
+```text
+zui/
+├── frontend/               # React SPA (Vite, TypeScript)
+│   ├── src/
+│   │   ├── main.tsx            # Entry point: registers node/config types, mounts React
+│   │   ├── app/
+│   │   │   ├── canvas/         # Core graph editor (React Flow + Zustand)
+│   │   │   ├── kosmos/         # Platform shell: sidebar, recollection list, AI settings
+│   │   │   └── recollections/  # Logos (rich text), Flux (canvas), Katalogos (gallery)
+│   │   ├── components/
+│   │   │   ├── graph/          # AnimatedEdge, BaseNode, handles, keyboard shortcuts
+│   │   │   ├── nodes/          # One folder per node type (agent, config, variable, …)
+│   │   │   └── ui/             # Shadcn-based primitives
+│   │   ├── hooks/              # Custom React hooks
+│   │   └── lib/
+│   │       └── graph/          # Registry, types, state, rendering pipeline, Nunjucks utils
+│   ├── Dockerfile              # Multi-stage: Vite build → Nginx
+│   ├── Dockerfile.dev          # Dev with hot reload
+│   ├── nginx.conf
+│   └── package.json
+├── backend/                # Node.js/Express API
+│   ├── src/
+│   │   ├── index.ts            # Express entry: registers routes, CORS, error handler
+│   │   ├── routes/agentRoutes.ts
+│   │   ├── services/agentService.ts
+│   │   ├── repositories/cacheRepository.ts
+│   │   ├── models/index.ts
+│   │   └── middleware/rateLimiter.ts
+│   └── package.json
+├── docs/
+│   ├── ARCHITECTURE.md
+│   ├── PERFORMANCE.md
+│   ├── NODE_TYPE_EXTENSIBILITY_PROPOSAL.md
+│   └── CODE_REVIEW_CHECKLIST.md
+├── docker-compose.yml
+└── .gitignore
+```
+
+Ignored by git: `node_modules`, `dist`, `.env`, `.env.*`. Local Docker overrides: `docker-compose.override.yml` (optional, not committed).
+
+---
+
+## Run locally (dev)
+
+**Frontend only** (no AI agent):
+
+```bash
+cd frontend && npm install && npm run dev
+# → http://localhost:3000
+```
+
+**Frontend + backend** (for AI agent and health check):
+
+```bash
+# Terminal 1 – backend
+cd backend && npm install && npm run dev
+# → http://localhost:8080
+
+# Terminal 2 – frontend
+cd frontend && npm install && npm run dev
+# → http://localhost:3000  (Vite proxies /api/* and /health to backend)
+```
+
+---
+
+## Run with Docker
+
+```bash
+docker compose up --build
+```
+
+- **Frontend**: <http://localhost:3000> (Nginx; `/api/*` proxied to backend).
+- **Backend**: <http://localhost:8080> (Express).
+
+Environment variables (backend service):
+
+| Variable         | Default                   | Description                                |
+|------------------|---------------------------|--------------------------------------------|
+| `PORT`           | `8080`                    | Backend listen port.                       |
+| `CORS_ORIGIN`    | `http://localhost:3000`   | Allowed origin for CORS.                   |
+| `AI_BASE_URL`    | *(unset)*                 | OpenAI-compatible base URL (local LLMs).   |
+| `AI_MODEL`       | `gpt-4o-mini`             | Model ID for the AI agent.                 |
+| `OPENAI_API_KEY` | *(unset)*                 | Required when using OpenAI directly.       |
+
+For self-hosting (e.g., Tailscale/HTTPS): set `CORS_ORIGIN` to your frontend URL and put Caddy or Nginx in front for TLS.
+
+---
+
+## Scripts
+
+| Command                              | Description                            |
+|--------------------------------------|----------------------------------------|
+| `cd frontend && npm run dev`         | Vite dev server (port 3000).           |
+| `cd frontend && npm run build`       | Build frontend for production.         |
+| `cd frontend && npm run preview`     | Preview production build.              |
+| `cd frontend && npm run test`        | Run tests in watch mode (Vitest).      |
+| `cd frontend && npm run test:run`    | Run tests once (CI).                   |
+| `cd backend && npm run dev`          | Backend with `tsx --watch`.            |
+| `cd backend && npm start`            | Backend production run.                |
+| `docker compose up --build`          | Run full stack in Docker.              |
+
+---
+
+## Backend API
+
+| Method | Path                  | Body / Response                                                                 |
+|--------|-----------------------|---------------------------------------------------------------------------------|
+| GET    | `/health`             | `{ ok: true, timestamp: number }` — health check for Docker/orchestration.      |
+| POST   | `/api/agent`          | Body `{ prompt, context?, contextNodes? }` → `{ markdown }` (one-shot).         |
+| POST   | `/api/agent/stream`   | Body `{ prompt, context?, contextNodes? }` → SSE text stream (streaming).       |
+
+---
+
+## Agent node (local LLM or OpenAI)
+
+AI connection settings are configured **directly in the UI** — open the sidebar and go to **AI Settings**. You can switch between providers without restarting the server.
+
+The backend reads its AI config from environment variables as a fallback:
+
+### Local LLM (e.g. LM Studio)
+
+1. Install [LM Studio](https://lmstudio.ai/), load a model, and start the local server (default: `http://localhost:1234`).
+2. Set env vars (backend):
+
+   ```bash
+   export AI_BASE_URL=http://localhost:1234/v1
+   export AI_MODEL=your-model-name   # optional; matches the name shown in LM Studio
+   ```
+
+### OpenAI
+
+```bash
+export OPENAI_API_KEY=sk-...
+export AI_MODEL=gpt-4o-mini   # optional; defaults to gpt-4o-mini
+```
+
+---
+
+## Contribute
+
+- [ARCHITECTURE.md](ARCHITECTURE.md) — architecture overview, key patterns, module map
+- [CONTRIBUTING.md](CONTRIBUTING.md) — coding standards, branch workflow, test commands
+- [PERFORMANCE_IMPROVEMENTS.md](PERFORMANCE_IMPROVEMENTS.md) — bottleneck analysis and improvement plan
+- [docs/CODE_REVIEW_CHECKLIST.md](docs/CODE_REVIEW_CHECKLIST.md) — PR review checklist
+- [docs/NODE_TYPE_EXTENSIBILITY_PROPOSAL.md](docs/NODE_TYPE_EXTENSIBILITY_PROPOSAL.md) — node plugin system design
+
+*Thank you for contributing!*

backend/.dockerignore

@@ -0,0 +1,5 @@
+node_modules
+.git
+*.log
+.env*
+.env.*

backend/.env.example

@@ -0,0 +1,14 @@
+# Optional: backend env vars. Copy to .env and adjust.
+
+# --- Agent (AI) ---
+# For OpenAI: set your key (model defaults to gpt-4o-mini).
+# OPENAI_API_KEY=sk-...
+
+# For local LLM (LM Studio, Ollama, etc.): set base URL. No API key required.
+# AI_BASE_URL=http://localhost:1234/v1
+# Optional: model name (LM Studio shows the loaded model id).
+# AI_MODEL=local-model
+
+# --- Server ---
+# PORT=8080
+# CORS_ORIGIN=http://localhost:3000

backend/Dockerfile

@@ -0,0 +1,21 @@
+# Single-stage, Alpine, Node 20. Production backend (no DB).
+FROM node:20-alpine
+
+WORKDIR /app
+
+# Dependencies only
+COPY package.json package-lock.json* ./
+RUN npm ci --omit=dev
+
+COPY src ./src
+
+# Non-root user
+RUN addgroup -g 1001 -S app && adduser -u 1001 -S app -G app
+USER app
+
+EXPOSE 8080
+
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+  CMD node -e "require('http').get('http://localhost:8080/health', (r) => process.exit(r.statusCode === 200 ? 0 : 1))"
+
+CMD ["node", "src/index.js"]

backend/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "zui-backend",
+  "version": "1.0.0",
+  "private": true,
+  "description": "Minimal Express API for Zui (agent, health; no DB)",
+  "type": "module",
+  "main": "src/index.ts",
+  "scripts": {
+    "start": "node src/index.ts",
+    "dev": "tsx watch src/index.ts",
+    "build": "tsc"
+  },
+  "engines": {
+    "node": ">=20"
+  },
+  "dependencies": {
+    "ai": "^4.0.0",
+    "@ai-sdk/openai": "^1.0.0",
+    "cors": "^2.8.5",
+    "express": "^4.21.0"
+  },
+  "devDependencies": {
+    "@types/cors": "^2.8.17",
+    "@types/express": "^5.0.0",
+    "@types/node": "^22.0.0",
+    "tsx": "^4.0.0",
+    "typescript": "^5.0.0"
+  }
+}

backend/src/index.ts

@@ -0,0 +1,102 @@
+/**
+ * Backend API: Layered architecture for scalability and maintainability.
+ * 
+ * ## Architecture Layers
+ * 
+ * ### Controllers (routes/)
+ * - Handle HTTP requests and responses
+ * - Validate input and format output
+ * - Call services for business logic
+ * 
+ * ### Services (services/)
+ * - Implement business logic
+ * - Coordinate between controllers and repositories
+ * - Handle validation and transformation
+ * 
+ * ### Repositories (repositories/)
+ * - Data access layer
+ * - Interact with databases or external APIs
+ * - Return domain models
+ * 
+ * ### Models (models/)
+ * - Data structures and types
+ * - Validation schemas
+ * 
+ * ### Middleware (middleware/)
+ * - Request validation
+ * - Authentication/authorization
+ * - Rate limiting
+ * - Error handling
+ * 
+ * ## Adding New Endpoints
+ * 
+ * 1. Define the model in `models/`
+ * 2. Implement repository logic in `repositories/`
+ * 3. Implement service logic in `services/`
+ * 4. Create controller in `routes/`
+ * 5. Register route in `index.ts`
+ */
+
+import express from 'express'
+import cors from 'cors'
+
+// ---------------------------------------------------------------------------
+// Configuration
+// ---------------------------------------------------------------------------
+
+const PORT = Number(process.env.PORT) || 8080
+const CORS_ORIGIN = process.env.CORS_ORIGIN || 'http://localhost:3000'
+
+// ---------------------------------------------------------------------------
+// Express App Setup
+// ---------------------------------------------------------------------------
+
+const app = express()
+
+app.use(cors({ origin: CORS_ORIGIN }))
+app.use(express.json())
+
+// ---------------------------------------------------------------------------
+// Agent Routes
+// ---------------------------------------------------------------------------
+
+import { handleAgentRequest, handleAgentStreamRequest } from './routes/agentRoutes.js'
+
+/** POST /api/agent - Run AI agent */
+app.post('/api/agent', handleAgentRequest)
+
+/** POST /api/agent/stream - Stream AI agent response */
+app.post('/api/agent/stream', handleAgentStreamRequest)
+
+// ---------------------------------------------------------------------------
+// Health Check Endpoint
+// ---------------------------------------------------------------------------
+
+/** GET /health - Health check for Docker / orchestration */
+app.get('/health', (req, res) => {
+  res.status(200).json({ ok: true, timestamp: Date.now() })
+})
+
+// ---------------------------------------------------------------------------
+// Error Handling Middleware
+// ---------------------------------------------------------------------------
+
+/** Global error handler for consistent error responses */
+app.use((err: Error, req: express.Request, res: express.Response, next: express.NextFunction) => {
+  console.error('Error:', err)
+  res.status(500).json({ error: err.message ?? 'Internal server error' })
+})
+
+// ---------------------------------------------------------------------------
+// Start Server
+// ---------------------------------------------------------------------------
+
+app.listen(PORT, '0.0.0.0', () => {
+  console.log(`Backend listening on port ${PORT} (CORS: ${CORS_ORIGIN})`)
+})
+
+// ---------------------------------------------------------------------------
+// Export for testing
+// ---------------------------------------------------------------------------
+
+export default app

backend/src/middleware/rateLimiter.ts

@@ -0,0 +1,88 @@
+/**
+ * Middleware: Rate limiting for API endpoints.
+ * 
+ * This module provides rate limiting middleware to protect the API
+ * from abuse and ensure fair usage.
+ */
+
+/**
+ * Rate limit configuration
+ */
+export type RateLimitConfig = {
+  /** Maximum number of requests allowed in the window */
+  max: number
+  /** Window size in milliseconds */
+  windowMs: number
+  /** Error message to return when rate limited */
+  message?: string
+}
+
+/**
+ * Default rate limit configuration
+ */
+export const DEFAULT_RATE_LIMIT_CONFIG: RateLimitConfig = {
+  max: 100,
+  windowMs: 60 * 1000, // 1 minute
+  message: 'Too many requests, please try again later.',
+}
+
+/**
+ * In-memory store for rate limiting
+ */
+const rateLimitStore = new Map<string, { count: number; resetTime: number }>()
+
+/**
+ * Rate limiting middleware
+ * 
+ * @param config - Rate limit configuration
+ * @returns Express middleware function
+ */
+export function rateLimit(config: RateLimitConfig = DEFAULT_RATE_LIMIT_CONFIG) {
+  return (req: { ip?: string; socket?: { remoteAddress?: string } }, res: { status: (code: number) => { json: (body: { error: string }) => void }, locals: Record<string, unknown> }, next: () => void): void => {
+    const ip = req.ip || req.socket?.remoteAddress || 'unknown'
+    const now = Date.now()
+    
+    let entry = rateLimitStore.get(ip)
+    
+    if (!entry || now > entry.resetTime) {
+      // Reset the counter for a new window
+      entry = { count: 1, resetTime: now + config.windowMs }
+      rateLimitStore.set(ip, entry)
+      next()
+      return
+    }
+    
+    entry.count++
+    
+    if (entry.count > config.max) {
+      res.status(429).json({ error: config.message ?? 'Too many requests' })
+      return
+    }
+    
+    next()
+  }
+}
+
+/**
+ * Clean up expired entries from the rate limit store
+ */
+export function cleanupRateLimitStore(): void {
+  const now = Date.now()
+  for (const [ip, entry] of rateLimitStore.entries()) {
+    if (now > entry.resetTime) {
+      rateLimitStore.delete(ip)
+    }
+  }
+}
+
+/**
+ * Get rate limit status for an IP
+ */
+export function getRateLimitStatus(ip: string): { remaining: number; resetTime: number } | null {
+  const entry = rateLimitStore.get(ip)
+  if (!entry) return null
+  return {
+    remaining: Math.max(0, DEFAULT_RATE_LIMIT_CONFIG.max - entry.count),
+    resetTime: entry.resetTime,
+  }
+}

backend/src/models/index.ts

@@ -0,0 +1,63 @@
+/**
+ * Models: Data structures and validation schemas.
+ * 
+ * This module defines the domain models used throughout the application.
+ */
+
+/**
+ * Agent request payload
+ */
+export type AgentRequest = {
+  prompt: string
+  context?: string
+  contextNodes?: AgentContextNode[]
+  connection?: AgentConnection
+  reasoning?: boolean
+}
+
+/**
+ * Context node for agent requests
+ */
+export type AgentContextNode = {
+  id: string
+  content?: string
+}
+
+/**
+ * AI connection configuration
+ */
+export type AgentConnection = {
+  provider: 'openai' | 'local'
+  baseURL?: string
+  apiKey?: string
+  model?: string
+}
+
+/**
+ * Agent response
+ */
+export type AgentResponse = {
+  markdown: string
+}
+
+/**
+ * Agent stream response
+ */
+export type AgentStreamResponse = {
+  markdown: string
+}
+
+/**
+ * Health check response
+ */
+export type HealthResponse = {
+  ok: boolean
+  timestamp: number
+}
+
+/**
+ * Error response
+ */
+export type ErrorResponse = {
+  error: string
+}

backend/src/repositories/cacheRepository.ts

@@ -0,0 +1,103 @@
+/**
+ * Repositories: Data access layer.
+ * 
+ * This module handles data persistence and retrieval.
+ * It abstracts the underlying storage mechanism.
+ */
+
+/**
+ * Cache entry for expensive computations
+ */
+export type CacheEntry<T> = {
+  /** Unique key for the cache entry */
+  key: string
+  /** Cached data */
+  data: T
+  /** Timestamp (ms) when this entry was created */
+  createdAt: number
+  /** Time-to-live in milliseconds */
+  ttl?: number
+}
+
+/**
+ * In-memory cache implementation
+ */
+export class InMemoryCache {
+  private cache = new Map<string, CacheEntry<unknown>>()
+  private defaultTtl = 5 * 60 * 1000 // 5 minutes
+
+  /**
+   * Get a value from the cache
+   * 
+   * @param key - Cache key
+   * @returns Cached value or null if not found or expired
+   */
+  get<T>(key: string): T | null {
+    const entry = this.cache.get(key) as CacheEntry<T> | undefined
+    if (!entry) return null
+    
+    // Check if entry has expired
+    if (entry.ttl && Date.now() - entry.createdAt > entry.ttl) {
+      this.cache.delete(key)
+      return null
+    }
+    
+    return entry.data
+  }
+
+  /**
+   * Set a value in the cache
+   * 
+   * @param key - Cache key
+   * @param data - Data to cache
+   * @param ttl - Optional time-to-live in milliseconds (uses default if not specified)
+   */
+  set<T>(key: string, data: T, ttl?: number): void {
+    this.cache.set(key, {
+      key,
+      data,
+      createdAt: Date.now(),
+      ttl: ttl ?? this.defaultTtl,
+    })
+  }
+
+  /**
+   * Delete a value from the cache
+   * 
+   * @param key - Cache key
+   */
+  delete(key: string): void {
+    this.cache.delete(key)
+  }
+
+  /**
+   * Clear all entries from the cache
+   */
+  clear(): void {
+    this.cache.clear()
+  }
+
+  /**
+   * Clean up expired entries
+   */
+  cleanup(): void {
+    const now = Date.now()
+    for (const [key, entry] of this.cache.entries()) {
+      if (entry.ttl && now - entry.createdAt > entry.ttl) {
+        this.cache.delete(key)
+      }
+    }
+  }
+
+  /**
+   * Get the number of entries in the cache
+   */
+  size(): number {
+    return this.cache.size
+  }
+}
+
+/**
+ * Global cache instance
+ */
+export const cache = new InMemoryCache()

backend/src/routes/agentRoutes.ts

@@ -0,0 +1,72 @@
+/**
+ * Routes: HTTP request handlers.
+ * 
+ * This module contains the route handlers for the API.
+ * Routes validate input and format output, then call services for business logic.
+ */
+
+import type { AgentRequest, AgentResponse, ErrorResponse } from '../models'
+
+/**
+ * POST /api/agent - Run AI agent
+ * 
+ * Request body: { prompt, context?, contextNodes?, connection? }
+ * Response: { markdown }
+ */
+export async function handleAgentRequest(req: any, res: any): Promise<void> {
+  try {
+    const body = req.body
+    const { buildAgentRequest } = await import('../services/agentService')
+    
+    const built = buildAgentRequest(body)
+    if ('error' in built) {
+      res.status(503).json({ error: built.error } as ErrorResponse)
+      return
+    }
+    
+    const { generateText } = await import('ai')
+    const result = await generateText({
+      model: built.openai as any,
+      prompt: built.fullPrompt,
+    })
+    
+    const { processAgentResponse } = await import('../services/agentService')
+    const response = processAgentResponse(result)
+    res.json(response)
+  } catch (err) {
+    console.error('Agent error:', err)
+    res.status(500).json({ error: (err as Error).message ?? 'Agent request failed' } as ErrorResponse)
+  }
+}
+
+/**
+ * POST /api/agent/stream - Stream AI agent response
+ * 
+ * Request body: { prompt, context?, contextNodes?, connection? }
+ * Response: plain text (markdown) chunks
+ */
+export async function handleAgentStreamRequest(req: any, res: any): Promise<void> {
+  try {
+    const body = req.body
+    const { buildAgentRequest } = await import('../services/agentService')
+    
+    const built = buildAgentRequest(body)
+    if ('error' in built) {
+      res.status(503).json({ error: built.error } as ErrorResponse)
+      return
+    }
+    
+    const { streamText } = await import('ai')
+    const result = streamText({
+      model: built.openai as any,
+      prompt: built.fullPrompt,
+    })
+    
+    res.setHeader('Content-Type', 'text/plain; charset=utf-8')
+    res.setHeader('Transfer-Encoding', 'chunked')
+    result.pipeTextStreamToResponse(res)
+  } catch (err) {
+    console.error('Agent stream error:', err)
+    res.status(500).json({ error: (err as Error).message ?? 'Agent request failed' } as ErrorResponse)
+  }
+}

backend/src/services/agentService.ts

@@ -0,0 +1,65 @@
+/**
+ * Services: Business logic layer.
+ * 
+ * This module contains the business logic for the application.
+ * Services coordinate between controllers and repositories.
+ */
+
+import type { AgentRequest, AgentResponse, AgentConnection } from '../models'
+
+/**
+ * Build OpenAI client and full prompt from request body.
+ * Returns { openai, modelId, fullPrompt } or { error }.
+ */
+export function buildAgentRequest(body: AgentRequest): { openai: unknown; modelId: string; fullPrompt: string } | { error: string } {
+  const { prompt, context, contextNodes, connection: conn, reasoning } = body ?? {}
+  const reasoningEnabled = Boolean(reasoning)
+  let baseURL = process.env.AI_BASE_URL?.trim() || null
+  let apiKey = process.env.OPENAI_API_KEY?.trim() || null
+  let modelId = process.env.AI_MODEL?.trim() || (baseURL ? 'local-model' : 'gpt-4o-mini')
+  
+  if (conn && typeof conn === 'object') {
+    const c = conn as AgentConnection
+    const provider = c.provider === 'openai' ? 'openai' : 'local'
+    if (provider === 'local') {
+      baseURL = (typeof c.baseURL === 'string' && c.baseURL.trim()) ? c.baseURL.trim() : baseURL
+      apiKey = (typeof c.apiKey === 'string' && c.apiKey.trim()) ? c.apiKey.trim() : (apiKey || 'lm-studio')
+    } else {
+      baseURL = null
+      apiKey = (typeof c.apiKey === 'string' && c.apiKey.trim()) ? c.apiKey.trim() : apiKey
+    }
+    if (typeof c.model === 'string' && c.model.trim()) modelId = c.model.trim()
+  }
+  
+  if (!baseURL && !apiKey) {
+    return { error: 'No AI configured. Set connection in Settings (AI) or env: OPENAI_API_KEY or AI_BASE_URL.' }
+  }
+  
+  const basePrompt = [
+    typeof prompt === 'string' ? prompt : 'No prompt provided.',
+    context && typeof context === 'string' ? `\n\nAdditional context:\n${context}` : '',
+    Array.isArray(contextNodes) && contextNodes.length > 0
+      ? `\n\nContext from connected nodes:\n${contextNodes.map((n) => (n.content != null ? n.content : `${n.id}: (no content)`)).join('\n\n')}`
+      : '',
+  ].join('')
+  
+  const fullPrompt = reasoningEnabled
+    ? basePrompt + '\n\nRespond in exactly two markdown sections. First: "## Reasoning" with your step-by-step reasoning. Then: "## Output" with only the final answer. No preamble.'
+    : basePrompt + '\n\nRespond with structured markdown only. No preamble.'
+  
+  const { createOpenAI } = require('@ai-sdk/openai')
+  const openai = createOpenAI({
+    apiKey: apiKey || 'lm-studio',
+    ...(baseURL && { baseURL, compatibility: 'compatible' }),
+  })
+  
+  return { openai, modelId, fullPrompt }
+}
+
+/**
+ * Process agent response
+ */
+export function processAgentResponse(result: { text?: string }): AgentResponse {
+  const markdown = result?.text ?? ''
+  return { markdown }
+}

backend/tsconfig.json

@@ -0,0 +1,20 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "types": ["node"]
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}

docker-compose.yml

@@ -0,0 +1,40 @@
+# Zui: frontend (Nginx) + backend (Express). No DB.
+# Usage: docker compose up --build
+# Dev with hot reload: use frontend/Dockerfile.dev and mount ./frontend, or run npm run dev locally.
+
+services:
+  frontend:
+    build:
+      context: ./frontend
+      dockerfile: Dockerfile
+    ports:
+      - "3000:80"
+    depends_on:
+      backend:
+        condition: service_healthy
+    environment:
+      - VITE_API_URL=http://localhost:8080
+    networks:
+      - app
+
+  backend:
+    build:
+      context: ./backend
+      dockerfile: Dockerfile
+    ports:
+      - "8080:8080"
+    environment:
+      - PORT=8080
+      - CORS_ORIGIN=http://localhost:3000
+    healthcheck:
+      test: ["CMD", "node", "-e", "require('http').get('http://localhost:8080/health', (r) => process.exit(r.statusCode === 200 ? 0 : 1))"]
+      interval: 30s
+      timeout: 3s
+      start_period: 5s
+      retries: 3
+    networks:
+      - app
+
+networks:
+  app:
+    driver: bridge

docs/CODE_REVIEW_CHECKLIST.md

@@ -0,0 +1,48 @@
+# Code Review Checklist
+
+Use this checklist during code reviews to ensure high standards of readability, maintainability, and performance.
+
+## 1. Readability
+
+- [ ] **Naming**: Variables, functions, and components use descriptive, consistent names (camelCase for functions/variables, PascalCase for components).
+- [ ] **JSDoc**: All public APIs have complete JSDoc comments with `@param`, `@returns`, and `@example` tags.
+- [ ] **Line Length**: No line exceeds 120 characters; wrap long lines for readability.
+- [ ] **Comments**: Explain *why* something is done, not just *what* is done. Avoid redundant comments.
+- [ ] **Whitespace**: Consistent spacing and indentation (2 spaces for TypeScript/JSX).
+
+## 2. Maintainability
+
+- [ ] **Component Structure**: Large components are split into smaller, focused sub‑components.
+- [ ] **Hooks**: Custom hooks encapsulate reusable logic and are named with `use` prefix.
+- [ ] **Utility Functions**: Pure functions live in `src/lib/` and are exported for reuse.
+- [ ] **Type Safety**: All function signatures include explicit TypeScript types; no `any` usage.
+- [ ] **Import Order**: Core → Library → Project → Relative imports; alphabetical within groups.
+
+## 3. Performance
+
+- [ ] **Memoization**: Expensive calculations use `useMemo`; event handlers use `useCallback`.
+- [ ] **Lazy Loading**: Heavy modules are loaded via `import()`; code splitting is configured in Vite.
+- [ ] **Virtualization**: Large lists use `react-window` or similar for efficient rendering.
+- [ ] **State Granularity**: State updates target only the minimal portion of state; avoid unnecessary re‑renders.
+- [ ] **Bundle Size**: No unused dependencies; assets are compressed (gzip/brotli) in production.
+
+## 4. Accessibility & Security
+
+- [ ] **ARIA**: Semantic HTML and ARIA attributes are present for interactive elements.
+- [ ] **Input Validation**: User inputs are validated before processing; no hard‑coded secrets.
+- [ ] **Error Handling**: Errors are caught and logged appropriately; user‑friendly messages are shown.
+
+## 5. Testing
+
+- [ ] **Unit Tests**: Cover all new logic with tests; aim for ≥ 80 % coverage on critical paths.
+- [ ] **Integration Tests**: Verify that components interact correctly with state/store.
+- [ ] **Test Naming**: Test files end with `.test.tsx` and describe the behavior being tested.
+
+## 6. Documentation Links
+
+- [ ] Architecture Overview: [[ARCHITECTURE.md](ARCHITECTURE.md)]
+- [ ] Performance Plan: [[PERFORMANCE_IMPROVEMENTS.md](PERFORMANCE_IMPROVEMENTS.md)]
+- [ ] Junior Developer Quickstart: [[QUICKSTART_FOR_JUNIORS.md](QUICKSTART_FOR_JUNIORS.md)]
+- [ ] Contribution Guide: [[CONTRIBUTING.md](CONTRIBUTING.md)]
+
+*Reviewers should mark any failing items as **[ ]** and request changes before approving.*

docs/NODE_TYPE_EXTENSIBILITY_PROPOSAL.md

@@ -0,0 +1,101 @@
+# Node Type Extensibility — Proposal
+
+## Goal
+
+Allow developers to add new node types and their rendering/logic without editing core app code. Each new type should provide: its React component, default data/style, connection rules, help text, and context-menu entry.
+
+## Current State
+
+- **Registration:** In `App.tsx`, `nodeTypes` is a hardcoded map (config → ConfigNode, render → RenderingNode, etc.).
+- **Defaults & IDs:** `flowUtils.ts` has `PREFIX_BY_TYPE`, `DEFAULT_NODE_STYLE`, `DEFAULT_DATA`, `getDefaultDataForType`, `getResetDataForType` — all branch on type.
+- **Validation:** `isValidConnection` in `App.tsx` encodes rules (e.g. nothing → variable, only config → render) with explicit type checks.
+- **UI:** Context menu “Create node” items, paste allowlist (`VALID_NODE_TYPES`), node help (`nodeHelp.tsx`), footer indicators (`NODE_HAS_INPUT` / `NODE_HAS_OUTPUT`), and `NodeMenubar` / `AnimatedEdge` use type strings or fixed type unions.
+
+Adding a fifth type today requires editing App, flowUtils, nodeHelp, NodeFooterEdgeIndicators, and possibly NodeMenubar/AnimatedEdge.
+
+---
+
+## Alternative 1: Central Node Type Registry (single module)
+
+**Idea:** One module (e.g. `src/lib/nodeRegistry.ts` or `src/config/nodeTypes.ts`) holds a **single registry object** keyed by type id. Each entry describes the type:
+
+- `component` — React component for the node
+- `defaultStyle`, `defaultData`, `idPrefix`
+- `hasInput` / `hasOutput` (for footer and validation)
+- `allowedSourceTypes` / `allowedTargetTypes` (for connection validation)
+- `help` (title + content for NodeHelpPopover)
+- `menuLabel`, `menuIcon` (for context menu “Create node”)
+
+App and other consumers **import the registry** and iterate: build `nodeTypes` from registry, build context menu from registry, call `getDefaultDataForType(registry, type)`, and run connection validation using registry metadata.
+
+**Pros:** Single source of truth; no new concepts (no plugins).  
+**Cons:** Extensions still require editing that one file (or a dedicated “contrib” section inside it). Good for a small, curated set of types.
+
+---
+
+## Alternative 2: Plugin / Contribution API (mutable registry + `registerNodeType()`)
+
+**Idea:** The registry is **mutable**. A bootstrap phase (e.g. in `main.tsx` or a dedicated `registerBuiltinNodes.ts`) calls `registerNodeType(descriptor)` for each built-in type. Third-party code (or feature modules) can call the same API to add types without touching the core registry module.
+
+- Export `registerNodeType(descriptor: NodeTypeDescriptor)` and `getRegisteredNodeTypes()` (and optionally `getNodeType(id)`).
+- Descriptor shape: same as in Alternative 1 (component, defaults, connection rules, help, menu).
+- Built-in types are registered at app init; the registry is then read-only for the rest of the session (or remains open for dynamic plugins).
+
+**Pros:** True extensibility: new types = call `registerNodeType` (e.g. from a separate package or an async-loaded chunk).  
+**Cons:** Need a clear descriptor type and lifecycle (when registration runs, ordering). Slightly more indirection when reading “what types exist.”
+
+---
+
+## Alternative 3: Convention-based discovery (folder or config)
+
+**Idea:** Node types are **discovered** from the filesystem or a config file.
+
+- **Variant A:** Each type lives under a folder, e.g. `src/nodes/<typeId>/index.ts` exporting a descriptor. A loader (at build or runtime) imports all and registers them.
+- **Variant B:** A config file (e.g. `nodeTypes.config.ts`) lists type ids and module paths; the app dynamically imports and registers them.
+
+**Pros:** “Add a folder” or “add a line” to add a type; no direct call to a central registry from feature code.  
+**Cons:** Build/runtime setup (e.g. `import.meta.glob` or dynamic `import()`), ordering and error handling. May be overkill for an in-repo extension story.
+
+---
+
+## Recommendation
+
+**Use Alternative 2 (Plugin / Contribution API)** with a single registry module:
+
+1. **Define** a `NodeTypeDescriptor` type and a small API: `registerNodeType(descriptor)`, `getRegisteredNodeTypes()`, `getNodeType(id)`.
+2. **Move** all type-specific data (component, defaultStyle, defaultData, idPrefix, hasInput, hasOutput, connection rules, help, menu label/icon) into the descriptor. Connection rules can be expressed as `allowedSourceTypes` / `allowedTargetTypes` so validation is data-driven.
+3. **Register** the four built-in types (config, render, variable, function) at startup from a single “builtin” registration file (or from within the registry module). No change to the public shape of existing components; they are just passed to `registerNodeType`.
+4. **Refactor** App, flowUtils, nodeHelp, NodeFooterEdgeIndicators, and related UI to use the registry: `nodeTypes` and context menu from `getRegisteredNodeTypes()`, defaults and validation from descriptor, help from descriptor (or still from a function that reads descriptor.help).
+5. **Result:** Adding a fifth type = implement a component + call `registerNodeType({ id: 'mytype', component: MyNode, ... })` (e.g. in a feature module or a separate entry that runs before the app). No edits to App’s branching logic or to flowUtils/nodeHelp’s type unions.
+
+Optional follow-ups: move help content into the descriptor (so `nodeHelp.tsx` only re-exports from registry), and add a small “node type list” config so the context menu order is explicit.
+
+---
+
+## Implementation outline (Alternative 2)
+
+- **New:** `src/lib/nodeRegistry.ts` — `NodeTypeDescriptor` type, `registerNodeType()`, `getRegisteredNodeTypes()`, `getNodeType(id)`. Help content can live in the descriptor or be merged from current `nodeHelp.tsx` for built-ins.
+- **New (optional):** `src/lib/registerBuiltinNodes.ts` — imports ConfigNode, RenderingNode, VariableNode, FunctionNode and their help/defaults, calls `registerNodeType` for each; invoked from `main.tsx` before React render.
+- **Refactor:** `flowUtils.ts` — `getDefaultDataForType`, `getResetDataForType`, `DEFAULT_NODE_STYLE`, `PREFIX_BY_TYPE` (and `getNextNodeId`) take type and optionally the registry, or read from registry when called (registry imported inside flowUtils). Prefer: registry holds defaults/prefix; flowUtils exports thin wrappers that use registry.
+- **Refactor:** `App.tsx` — `nodeTypes` from `getRegisteredNodeTypes().map(...)`, context menu from same, `createNode`/paste use registry for valid types and defaults, `isValidConnection` uses descriptor’s `allowedSourceTypes`/`allowedTargetTypes`.
+- **Refactor:** `nodeHelp.tsx` — `getNodeHelp(type)` returns descriptor.help from registry (built-ins register help in descriptor).
+- **Refactor:** `NodeFooterEdgeIndicators.tsx` — `hasInput`/`hasOutput` from descriptor.
+- **Refactor:** `NodeMenubar` / `NodeHelpPopover` — keep `nodeType` as string; descriptor is looked up by id where needed.
+- **Refactor:** `AnimatedEdge` — edge label by target type can stay as a small map or move to descriptor (e.g. `connectionLabel?: string` when this type is target).
+
+After this, a new node type is added by: (1) implementing a React component, (2) calling `registerNodeType({ id: 'mytype', component: MyNode, ... })` at app init.
+
+---
+
+## Implemented (Alternative 2)
+
+- **`src/lib/nodeRegistry.ts`** — `NodeTypeDescriptor`, `registerNodeType()`, `getRegisteredNodeTypes()`, `getNodeType()`, `getDefaultDataForType()`, `getResetDataForType()`, `getIdPrefix()`, `getDefaultStyle()`, `isConnectionAllowed()`, `getConnectionLabelForTarget()`, `getNodeHelp()`.
+- **`src/lib/registerBuiltinNodes.tsx`** — Registers config, render, variable, function; invoked from `main.tsx` before render.
+- **`src/lib/flowUtils.ts`** — `getNextNodeId()` uses registry; default/reset data delegate to registry.
+- **App, NodeHelpPopover, NodeFooterEdgeIndicators, NodeMenubar, AnimatedEdge** — Use registry for types, validation, help, and UI.
+
+### Adding a new node type
+
+1. Implement a React component that accepts React Flow node props.
+2. Call `registerNodeType({ id, component, defaultStyle, defaultData, idPrefix, hasInput, hasOutput, allowedSourceTypes?, allowedTargetTypes?, help, menuLabel, menuIcon, ... })` from a module that runs at startup (e.g. imported and called from `main.tsx`).
+3. No edits to `App.tsx` or core flow/utils are required.

frontend/.dockerignore

@@ -0,0 +1,26 @@
+# Dependencies and build output
+node_modules
+dist
+
+# Git and env
+.git
+.gitignore
+.env*
+!.env.example
+
+# IDE, OS, logs
+.idea
+.vscode
+*.log
+.DS_Store
+
+# Tests (keep image small)
+**/__tests__
+**/*.test.ts
+**/*.test.tsx
+**/*.spec.ts
+**/*.spec.tsx
+coverage
+
+# Dev Dockerfile not needed in prod image
+Dockerfile.dev

frontend/Dockerfile

@@ -0,0 +1,21 @@
+# Multi-stage: build Vite app, then serve with Nginx (Alpine).
+# Frontend only; backend is a separate service.
+
+# Stage 1: build
+FROM node:20-alpine AS builder
+WORKDIR /app
+
+COPY package.json package-lock.json* ./
+RUN npm ci
+
+COPY . .
+RUN npm run build
+
+# Stage 2: serve
+FROM nginx:alpine
+COPY --from=builder /app/dist /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 80
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+  CMD wget -q -O /dev/null http://localhost:80/ || exit 1
+CMD ["nginx", "-g", "daemon off;"]

frontend/Dockerfile.dev

@@ -0,0 +1,12 @@
+# Dev image: run Vite with hot reload. Mount source as volume.
+FROM node:20-alpine
+
+WORKDIR /app
+
+COPY package.json package-lock.json* ./
+RUN npm ci
+
+# App code is mounted; no COPY so edits trigger reload
+EXPOSE 3000
+
+CMD ["npm", "run", "dev", "--", "--host", "0.0.0.0"]

frontend/docs/CANVAS_PERFORMANCE_OPTIONS.md

@@ -0,0 +1,185 @@
+# Canvas performance: options and refactoring for scalability
+
+This document lists **concrete options** to improve canvas (React Flow graph editor) performance, with design patterns and refactoring for scalability. Implement in order of impact vs effort; measure before/after where possible.
+
+---
+
+## 1. Stabilize `nodes` passed to React Flow (high impact, low effort)
+
+**Problem:** In `CanvasPage.tsx`, nodes are passed as:
+
+```ts
+nodes={nodes.map((n) => ({ ...n, className: [n.className, 'nowheel'].filter(Boolean).join(' ') }))}
+```
+
+Every render creates a **new array and new object references** for every node. React Flow may re-render or reconcile more than needed.
+
+**Options:**
+
+- **A. Compute derived props in a `useMemo`**  
+  Memoize the mapped nodes; depend only on `nodes` and a stable `className` suffix so the reference changes only when `nodes` actually changes.
+
+- **B. Avoid mutating node shape in the parent**  
+  Apply the `nowheel` class via `nodeTypes` default or a wrapper so you can pass `nodes={nodes}` directly. Keeps a single source of truth and avoids creating new node objects every render.
+
+**Pattern:** **Single source of truth** — avoid deriving a new structure on every render when the same structure can be expressed at the data or type level.
+
+---
+
+## 2. Split FlowContext to reduce consumer re-renders (high impact, medium effort)
+
+**Problem:** `FlowContext` holds graph state (`nodes`, `edges`, setters), connection path state (trigger/updating/paused/error sets and callbacks), and UI state (renaming, fullscreen, connectionFrom, etc.). Any change to any part creates a **new context value**, so **every node and every edge** that uses `useContext(FlowContext)` re-renders on any graph or path update.
+
+**Options:**
+
+- **A. Split into multiple contexts (recommended)**  
+  - **GraphContext:** `nodes`, `edges`, `setNodes`, `setEdges`, `applyGraph`, etc.  
+  - **ConnectionPathContext:** path node IDs, trigger/updating/paused/error state and callbacks.  
+  - **FlowUIContext:** `renamingNodeId`, `fullscreenNodeId`, `connectionFrom`, `flowActionsRef`, `isValidConnection`.  
+
+  Nodes that only need graph + UI (e.g. for `updateData`, `setFullscreenNodeId`) don’t re-render when only connection path state changes. Edges that only need connection path state don’t re-render when only `nodes`/`edges` change (e.g. drag position).
+
+- **B. Context + selectors**  
+  Keep a single store (e.g. Zustand) and have nodes/edges subscribe with selectors (e.g. `useStore(selector)`). Only re-render when the selected slice changes. This is a larger refactor but scales well.
+
+**Pattern:** **Segregation of concerns** — separate contexts (or stores) by update frequency and by consumer type so that high-frequency updates (e.g. connection path ticks) don’t force re-renders of all nodes/edges.
+
+---
+
+## 3. Memoize edge component and narrow its context usage (high impact, low effort)
+
+**Problem:** `AnimatedEdge` uses `useContext(FlowContext)` and reads `nodes`, `connectionPathNodeIds`, `connectionPathPausedSegmentNodeIds`, `connectionPathActiveSegmentNodeIds`, `connectionPathErrorNodeIds`. So every edge re-renders whenever the whole context value changes (e.g. any node move or path update).
+
+**Options:**
+
+- **A. Wrap `AnimatedEdge` in `React.memo`**  
+  Use a custom comparison that returns true when `id`, `source`, `target`, positions, and style haven’t changed. React Flow already passes stable edge props; memo avoids re-renders when parent re-renders with the same props.
+
+- **B. Feed only connection path data into edges**  
+  After splitting context (see §2), edges consume only **ConnectionPathContext**. Then they re-render only when path/trigger/updating/paused/error state changes, not on every `nodes`/`edges` change.
+
+- **C. Pass path state via React Flow edge `data`**  
+  Compute per-edge “connection status” (or relevant path IDs) in the canvas and pass it as `edge.data`. Edges become pure in terms of context: they only need `data` and standard edge props. Pushing the computation to the parent is one place to update when path state changes.
+
+**Pattern:** **Minimize subscriber set** — each component should subscribe only to the minimal state it needs (context split or selectors), and be memoized so parent re-renders don’t force unnecessary work.
+
+---
+
+## 4. Reduce history and save cost (medium impact, medium effort)
+
+**Problem:** In `useGraphStateWithHistory`, every `setNodes` / `setEdges` call runs `cloneState()`, which deep-clones all nodes and edges. With many nodes or large `node.data`, this is expensive. In `useCanvasGraph`, the save effect runs on every `nodes`/`edges` change (with a 500 ms debounce), so frequent updates (e.g. drag) still schedule many saves.
+
+**Options:**
+
+- **A. Structural sharing / copy-on-write**  
+  Keep history as immutable updates (e.g. only store changed nodes/edges or patches) instead of full clones. On undo/redo, apply patches or merge with previous state. This reduces both memory and CPU for large graphs.
+
+- **B. Throttle or idle-based save**  
+  Besides debouncing, only call `saveGraphToStorage` when the graph hasn’t changed for N seconds or when `requestIdleCallback` fires. Reduces work during continuous interaction.
+
+- **C. Limit history size and clone only when necessary**  
+  You already cap history (e.g. `MAX_HISTORY`). Ensure `cloneState` is only called when pushing to history, not on silent updates (e.g. drag). You already use `setNodesSilent` for drag; double-check that no accidental pushes happen during drag.
+
+**Pattern:** **Immutability with minimal copying** — use structural sharing or patch-based history so that only changed parts of the graph are copied and stored.
+
+---
+
+## 5. Contextual zoom and viewport (medium impact, low–medium effort)
+
+**Problem:** `ContextualZoomNode` uses `useViewport()` from React Flow. Viewport (zoom/pan) updates can trigger re-renders of **every** contextual node when zoom crosses the compact threshold.
+
+**Options:**
+
+- **A. Subscribe only near threshold**  
+  If the library allows, subscribe to viewport only when zoom is near `CONTEXTUAL_ZOOM_THRESHOLD` so small zoom changes don’t re-render all nodes. If not, consider throttling viewport updates before passing to context.
+
+- **B. Use a single “display mode” in context**  
+  One component (e.g. canvas container) subscribes to viewport and sets a value like `displayMode: 'compact' | 'full'` in context. Nodes only consume that enum; they don’t subscribe to raw zoom. Fewer subscribers and simpler logic.
+
+- **C. Keep current behavior but ensure nodes are memoized**  
+  With `createContextualNode`, the inner node is already wrapped (e.g. via `createAbstractNodeComponent`). Ensure the outer wrapper doesn’t break memo (e.g. avoid passing new object/function refs from viewport into the inner node).
+
+**Pattern:** **Facade / single subscriber** — one place turns “viewport” into a coarse decision (e.g. compact vs full); the rest of the tree depends only on that decision.
+
+---
+
+## 6. React Flow configuration (medium impact, low effort)
+
+**Problem:** Defaults may render or update more than needed for large graphs.
+
+**Options:**
+
+- **A. Enable `onlyRenderVisibleElements`**  
+  When supported and stable in your version, enable it so nodes (and optionally edges) outside the viewport are not rendered. Best combined with fixed node dimensions and explicit handle positions so edges still draw correctly when nodes are off-screen.
+
+- **B. Set `nodeOrigin`**  
+  If you use a consistent origin (e.g. top-left) for all nodes, set `nodeOrigin` so React Flow doesn’t have to infer it; can help with layout and hit-testing.
+
+- **C. Reduce MiniMap/Background work**  
+  If the minimap or background is expensive, consider making them optional (e.g. only when node count > N) or simplifying their rendering (e.g. simpler background pattern, minimap with lower refresh rate).
+
+**Pattern:** **Use platform features** — lean on React Flow’s built-in options (visibility culling, nodeOrigin) before adding custom virtualization.
+
+---
+
+## 7. Heavy node components (e.g. RenderingNode) (medium impact, medium effort)
+
+**Problem:** Nodes that run the resolve → render pipeline (e.g. `useRenderingNodeState`) do a lot of work: signatures, config resolution, rendering, connection path lifecycle. They already use `useAbstractNode` and memo via `createAbstractNodeComponent`; the main cost is internal (hooks, effects, possibly re-renders when context changes).
+
+**Options:**
+
+- **A. Ensure they only get connection path updates when relevant**  
+  After splitting context (§2), these nodes should only subscribe to graph + UI (and maybe a minimal connection path slice if they need to report “updating”/“paused”/“error”). They shouldn’t re-render on every path tick.
+
+- **B. Lazy or deferred computation**  
+  For heavy useMemos (e.g. `buildSourceSignatures`), consider `useDeferredValue` or moving work off the critical path (e.g. in a worker or requestIdleCallback) if the UI can show a stale state briefly.
+
+- **C. Virtualize or hide when not visible**  
+  Combined with `onlyRenderVisibleElements` or a custom “nodes in viewport” list, heavy nodes that are off-screen don’t mount at all, so their hooks and effects don’t run.
+
+**Pattern:** **Defer and cull** — avoid running expensive logic for nodes that are not visible or not relevant to the current interaction.
+
+---
+
+## 8. Node types and handlers (lower impact, low effort)
+
+**Problem:** `nodeTypes` and `edgeTypes` are already built with `useMemo` in `CanvasPage`. Handlers are mostly `useCallback`. Remaining issues are usually unstable references or unnecessary dependencies.
+
+**Options:**
+
+- **A. Keep `nodeTypes` / `edgeTypes` stable**  
+  Ensure `getRegisteredNodeTypes()` isn’t returning new array/object references every time; if it is, memoize at the registry level or in the hook that builds `nodeTypes`.
+
+- **B. Ensure `isValidConnection` doesn’t close over changing `nodes`**  
+  You already use `nodes` in `isValidConnection`; that’s correct for validation. If this callback is passed in context and triggers many re-renders, consider moving it to a ref (e.g. `isValidConnectionRef.current`) so the context value doesn’t change when `nodes` changes, and the validator always reads the latest nodes from the ref. Then nodes/edges that only need `isValidConnection` don’t re-render on every graph change.
+
+- **C. Memoize `defaultEdgeOptions` and `snapGrid`**  
+  You already have `defaultEdgeOptions = useMemo(() => ({ type: 'animated' }), [])` and `SNAP_GRID` constant. Keep that pattern for any other object/array props passed to `<ReactFlow>`.
+
+**Pattern:** **Stable references** — any prop or context value that is an object or function should be memoized or stored in a ref so that consumers don’t re-render unnecessarily.
+
+---
+
+## 9. Connection path hook (lower impact, already partially optimized)
+
+**Problem:** `useCanvasConnectionPath` derives `connectionPathNodeIds`, `connectionPathPausedSegmentNodeIds`, and `connectionPathActiveSegmentNodeIds` with `useMemo`; batching with `requestAnimationFrame` is already used for trigger updates. The main cost is that when this state changes, every edge (and possibly nodes using path role) re-renders if they all consume the same context.
+
+**Options:**
+
+- **A. After splitting context (§2), only edges (and path-aware nodes) subscribe to connection path context**  
+  Then path updates no longer force re-renders of nodes that don’t care about path.
+
+- **B. Keep derived sets in refs for equality checks**  
+  If the same set of IDs is produced repeatedly, avoid updating state (or context) when the set content is equal (e.g. compare `Array.from(set).sort().join(',')` or use a stable serialization) so that consumers don’t see a “new” reference and re-render.
+
+**Pattern:** **Stable outputs** — when feeding context or state, avoid new object/set/array references when the logical value hasn’t changed.
+
+---
+
+## Suggested order of implementation
+
+1. **Quick wins:** §1 (stabilize `nodes`), §3A (memoize `AnimatedEdge`), §6 (React Flow options), §8 (stable refs/callbacks).  
+2. **High leverage:** §2 (split FlowContext), then §3B/3C (edges consume only path state or `data`).  
+3. **Scalability:** §4 (history/save), §5 (viewport/contextual zoom), §7 (heavy nodes and visibility).
+
+This order keeps design patterns (context split, minimal subscription, stable references) consistent and sets you up for further scalability (e.g. more nodes, more edges, more complex node content) without large rewrites.

frontend/docs/CANVAS_STATE_DESIGN.md

@@ -0,0 +1,218 @@
+# Canvas state: design pattern for controlled, centralized, debuggable flow
+
+This doc proposes a **store + commands + selectors** pattern so canvas state is:
+
+- **Controlled** – every change goes through one place
+- **Centralized** – one store holds graph, path, and UI slices
+- **Predictable** – same action → same state transition; easy to reason about
+- **Easier to debug** – log commands, inspect store, optional time-travel
+
+It complements [CANVAS_PERFORMANCE_OPTIONS.md](./CANVAS_PERFORMANCE_OPTIONS.md) and [state.ts](../src/lib/graph/state.ts).
+
+---
+
+## 1. Core idea: single store + commands + selectors
+
+### 1.1 Single store (one source of truth)
+
+Keep all canvas-related state in **one store** with **slices**:
+
+```
+Store
+├── graph: { nodes, edges }           // current graph (with history if needed)
+├── path: ConnectionPathState         // trigger/updating/paused/error node IDs
+├── ui: FlowUIState                   // renaming, fullscreen, connectionFrom, etc.
+└── (optional) history: HistoryState  // undo/redo stack
+```
+
+- **No duplicate sources**: nodes/edges live only in the store, not in context + refs.
+- **Reads**: components get data via **selectors** (e.g. `useStore(s => s.graph.nodes)` or `useStore(selectPathForEdge, edgeId)`).
+- **Writes**: only via **commands** (e.g. `dispatch({ type: 'graph/setNodes', payload: updater })`).
+
+### 1.2 Commands (controlled mutations)
+
+Every mutation is a **command** (action):
+
+- **Graph**: `graph/setNodes`, `graph/setEdges`, `graph/applySilent` (position), `graph/undo`, `graph/redo`
+- **Path**: `path/addTrigger`, `path/startUpdate`, `path/endUpdate`, `path/setPaused`, `path/setError`
+- **UI**: `ui/setRenaming`, `ui/setFullscreen`, `ui/setConnectionFrom`
+
+Benefits:
+
+- **Predictable**: one command → one reducer → one new state; no scattered `setState` in hooks.
+- **Traceable**: log every command (and payload) in dev; replay or inspect.
+- **Testable**: test reducers with command + prev state → next state.
+- **Time-travel (optional)**: store past states or inverse deltas per command for debug UI.
+
+### 1.3 Selectors (derived state and subscriptions)
+
+**Selectors** are pure functions `(state) => value`. They:
+
+- **Derive** values (e.g. path node IDs from trigger/updating/paused).
+- **Scope** data (e.g. “incoming edges for node X”, “connection status for edge Y”).
+- **Stabilize** references when the logical value hasn’t changed (e.g. same path IDs → same Set reference).
+
+Components **subscribe via selectors**:
+
+- `useStore(selectGraph)` → re-render when `graph` slice changes.
+- `useStore(selectPathNodeIds)` → re-render only when path node IDs change.
+- `useStore(selectConnectionStatusForEdge, edgeId)` → re-render only when that edge’s status changes.
+
+So:
+
+- **Centralized**: all reads go through the store.
+- **Predictable**: same state in → same selector out.
+- **Performance**: only components whose selected value changed re-render (with a store that supports shallow equality, e.g. Zustand).
+
+---
+
+## 2. Data structures
+
+### 2.1 Store shape (TypeScript)
+
+```ts
+// Slices match current concepts; easy to migrate from existing state.ts + useCanvasConnectionPath.
+
+interface CanvasStore {
+  graph: {
+    nodes: AppNode[]
+    edges: AppEdge[]
+  }
+  path: ConnectionPathState   // from state.ts
+  ui: FlowUIState
+  // optional, for undo/redo
+  _history?: {
+    past: HistoryDelta[]
+    future: HistoryDelta[]
+  }
+}
+```
+
+### 2.2 Commands (discriminated union)
+
+```ts
+type CanvasCommand =
+  | { type: 'graph/setNodes'; payload: AppNode[] | ((prev: AppNode[]) => AppNode[]) }
+  | { type: 'graph/setEdges'; payload: AppEdge[] | ((prev: AppEdge[]) => AppEdge[]) }
+  | { type: 'graph/applySilent'; payload: (prev: GraphState) => GraphState }
+  | { type: 'path/addTrigger'; payload: string }
+  | { type: 'path/startUpdate'; payload: string }
+  | { type: 'path/endUpdate'; payload: string }
+  | { type: 'path/setPaused'; payload: { nodeId: string; paused: boolean } }
+  | { type: 'path/setError'; payload: { nodeId: string; error: boolean } }
+  | { type: 'ui/setRenaming'; payload: string | null }
+  | { type: 'ui/setFullscreen'; payload: string | null }
+  // ...
+```
+
+Single dispatcher:
+
+```ts
+function dispatch(cmd: CanvasCommand): void
+```
+
+### 2.3 Selectors (examples)
+
+```ts
+// Raw slices
+const selectGraph = (s: CanvasStore) => s.graph
+const selectPath = (s: CanvasStore) => s.path
+
+// Stable derived path sets (same ref if same IDs)
+const selectPathNodeIds = (s: CanvasStore) => getPathNodeIds(s.graph.edges, s.path...)
+
+// Per-edge status (for AnimatedEdge) – only changes when this edge’s status changes
+const selectConnectionStatusForEdge = (s: CanvasStore, source: string, target: string) =>
+  getConnectionStatus({ source, target, pathNodeIds: s.path.connectionPathNodeIds, ... })
+
+// Per-node: “am I on path?” (for BaseNode)
+const selectPathRoleForNode = (s: CanvasStore, nodeId: string) =>
+  getConnectionPathRole(nodeId, s.path)
+```
+
+Use with a store that supports **selector + equality** so components only re-render when the selected value actually changes (e.g. Zustand’s `useStore(selector, shallowEqual)` or custom `useSelector`).
+
+---
+
+## 3. Why this helps
+
+| Goal | How the pattern helps |
+|------|------------------------|
+| **Controlled** | All writes go through `dispatch(cmd)`. No ad-hoc `setState` in hooks or context. |
+| **Centralized** | One store; no split between context, refs, and local state for the same concept. |
+| **Predictable** | One command → one reducer → one new state. Order of updates is explicit. |
+| **Easier to debug** | Log commands; inspect store (e.g. Redux DevTools or a simple `store.getState()` logger); optional time-travel by replaying or reverting commands. |
+| **Fewer redraws** | Selectors + equality checks mean components only re-render when their slice or derived value changes. |
+| **Clear data flow** | Data flow is “store → selectors → components” and “events → commands → store”; no implicit propagation. |
+
+---
+
+## 4. Implementation options
+
+### Option A: Zustand (recommended for React)
+
+- **Store**: `create<CanvasStore>()` with a `dispatch` that applies commands and updates the store.
+- **Selectors**: `useCanvasStore(selectPathNodeIds)` etc.; Zustand re-renders only when the selected value changes (with shallow or custom equality).
+- **Commands**: either one `setState` that takes a reducer, or a separate `dispatch` that maps commands to `setState` calls.
+- **Debug**: middleware that logs commands and state (or use Redux DevTools with a small adapter).
+
+### Option B: Redux Toolkit
+
+- **Store**: one RTK store; slices: `graph`, `path`, `ui`.
+- **Commands**: RTK actions; reducers are pure and easy to test.
+- **Selectors**: `createSelector` for derived state; `useSelector` for subscriptions.
+- **Debug**: Redux DevTools out of the box (time-travel, action log, state diff).
+
+### Option C: Minimal custom store (no new deps)
+
+- **Store**: a single `useReducer` (or `useState` + reducer) at the top (e.g. CanvasPage or a provider).
+- **Commands**: dispatch to the reducer; reducer returns new state by slice.
+- **Selectors**: pass store (or state) to a `useSelector(store, selector, equality)` hook that subscribes and only re-renders when the selected value changes (e.g. by comparing with `Object.is` or shallow compare).
+- **Debug**: log `dispatch` and state in dev; optional snapshot history in the reducer.
+
+---
+
+## 5. Migration path from current setup
+
+1. **Introduce the store** (e.g. Zustand or RTK) next to existing context; keep feeding React Flow and current consumers from the store so behavior stays the same.
+2. **Move graph state** from `useGraphStateWithHistory` into the store (graph slice + history if needed); keep `setNodes`/`setEdges` as commands that update the store.
+3. **Move path state** from `useCanvasConnectionPath` into the store (path slice); replace path context with `useStore(selectPath...)` or per-edge/per-node selectors.
+4. **Move UI state** from CanvasPage `useState` into the store (ui slice); replace FlowUIContext with store selectors.
+5. **Remove redundant context** (GraphContext, ConnectionPathContext, FlowUIContext) once all reads go through selectors and all writes through commands.
+6. **Add logging / DevTools** for commands and state; add optional time-travel if desired.
+
+This can be done slice-by-slice (e.g. path first, then graph, then UI) to keep changes small and testable.
+
+---
+
+## 6. Implementation (Zustand)
+
+The store is implemented under `frontend/src/app/canvas/`:
+
+| File | Purpose |
+|------|---------|
+| `canvasStore.types.ts` | `CanvasStore`, `CanvasCommand`, slice types |
+| `canvasStore.reducer.ts` | Pure reducer + `initialCanvasStore` |
+| `canvasStore.selectors.ts` | Selectors (graph, path derived sets, per-edge status, per-node role) |
+| `canvasStore.ts` | Zustand store, `getCanvasStore()`, `dispatchCanvasCommand()`, `useCanvasStore()`, `useCanvasStoreDispatch()`; dev logging of commands |
+| `canvasStore.index.ts` | Re-exports for consumers |
+| `canvasStore.test.ts` | Test suite (reducer, selectors, store integration) |
+
+**Run tests:** `npm run test:run` (or `npm run test` for watch) in `frontend/`.
+
+**Usage:** Import from `@/app/canvas/canvasStore` or `@/app/canvas/canvasStore.index`:
+
+- `dispatchCanvasCommand({ type: 'graph/setNodes', payload: nodes })`
+- `useCanvasStore(selectPathNodeIds)` or `useCanvasStore(selectConnectionStatusForEdge, ...)` (selectors take state; for per-edge/per-node use a factory selector in the component)
+- `useCanvasStoreDispatch()` for stable dispatch in components
+
+Migration from existing context: feed the store from CanvasPage (or sync store ↔ existing hooks) and gradually replace context consumers with `useCanvasStore(selector)` and `dispatchCanvasCommand`. See §5 migration path.
+
+---
+
+## 7. Summary
+
+- **Pattern**: one **store** (graph + path + ui), **commands** for all mutations, **selectors** for reads and derived state.
+- **Data structures**: flat slices in the store; commands as a discriminated union; selectors as pure functions (state [, args]) → value.
+- **Benefits**: controlled, centralized, predictable, easier to debug, and fewer unnecessary redraws via selector-based subscriptions.
+- **Concrete next step**: migrate one consumer (e.g. AnimatedEdge) to `useCanvasStore(selectConnectionStatusForEdge)` with a per-edge selector and `dispatchCanvasCommand` for path updates; then remove its ConnectionPathContext dependency.

frontend/docs/IMPROVEMENTS.md

@@ -0,0 +1,77 @@
+# Codebase simplification and design patterns
+
+This doc summarizes recent improvements and suggested next steps for readability, extension, and consistency.
+
+## Done
+
+### 1. Single place for template/reachability (DRY)
+
+- **Added** `lib/graph/templateRefs.ts`: `isReachable`, `resolveExtendsRef`, `getTemplateRefs`.
+- **Refactored** `config/renderingLogic.ts` and `useRenderingNodeState.ts` to use these helpers instead of duplicating the same logic.
+- **Pattern:** Extract shared pure helpers into a small lib module; keep call sites thin and consistent.
+
+### 2. Naming and comments
+
+- **Renamed** `outputMenuRegistry.tsx` → `outputMenuHandlers.tsx` (no registry, only helpers).
+- **Updated** `rendering.ts` and `sourceRenderingLogic.ts`: output menu is described as coming from the node descriptor (`getOutputMenuContent`), not a separate registry.
+- **Documented** `NodeMenubar`: extra content can come from props or from the descriptor (`getNodeMenuExtraContent`).
+- **Documented** `nodeTypes.ts`: clarifies React Flow types vs node type id (nodeRegistry).
+
+### 3. Central pipeline entry
+
+- **rendering.ts** documents the 3-step pipeline, how to add a source/output type, and points to `templateRefs.ts` for shared helpers.
+
+### 4. Rendering signatures (pure module)
+
+- **Added** `lib/graph/renderingSignatures.ts`: `buildConnectedNodeIds`, `buildSourceSignatures` (connectedNodeIds + all five signatures + sourceSignature).
+- **Refactored** `useRenderingNodeState` to call `buildSourceSignatures` in a single useMemo; hook is shorter and signature logic is testable in isolation.
+
+### 5. Canvas split
+
+- **CanvasContextMenuContent** (`app/canvas/CanvasContextMenuContent.tsx`): context menu content (Create Node grouped by classification, Paste). CanvasPage passes `onCreateNode` and `onPaste`.
+- **useCanvasConnectionPath** (`app/canvas/useCanvasConnectionPath.ts`): all connection-path state and callbacks (updating/trigger/paused/error node ids, path node ids, start/end update, add/remove paused/error). CanvasPage calls the hook with `edges` and passes the result into FlowContext.
+
+### 6. useCanvasGraph and canvas graph utils
+
+- **canvasGraphUtils.ts**: `getExampleGraph()`, `getInitialGraph(projectId)` (load from storage or return example). Example nodes/edges live here.
+- **useCanvasGraph(projectId)**: wraps `useGraphStateWithHistory` with initial graph from `getInitialGraph(projectId)` and debounced save to storage when `projectId` is set. CanvasPage uses this instead of inline state + persistence.
+
+### 7. Config types registry
+
+- **configTypes.ts**: `configTypeRegistry` (Map), `registerConfigType(type)`, `getConfigTypes()`, `getConfigTypeIds()`, `registerBuiltinConfigTypes()`. Built-in types are in `BUILTIN_CONFIG_TYPES` and registered at app init. `getConfigType(id)` looks up in the registry; `getConfigTypeId(data)` uses registered ids. ConfigNode uses `getConfigTypes()` instead of `CONFIG_TYPES`. New output types can call `registerConfigType()` without editing the core array.
+
+### 8. Consistent NodeLike / EdgeLike
+
+- **templateRefs.ts**: `NodeLike` includes `type?: string`; both types documented. Single source of truth for minimal node/edge shape in the graph lib.
+- **sourceRenderingLogic**: context uses `NodeLike[]` and `EdgeLike[]` from templateRefs.
+- **renderingSignatures**: imports and re-exports `NodeLike` / `EdgeLike` from templateRefs; no local duplicate types.
+- **config/renderingLogic**: uses context nodes/edges directly (no casts); `setVarInContext(src: NodeLike)`.
+- **useRenderingNodeState**: casts to `NodeLike[]` / `EdgeLike[]` when calling `buildSourceSignatures` (types from renderingSignatures).
+
+### 9. Graph state, connection state, and node display state
+
+- **lib/graph/state.ts**: Central state contracts and flow doc.
+  - **GraphState** – in-memory nodes + edges (useGraphStateWithHistory, persisted by useCanvasGraph).
+  - **ConnectionPathState** – type describing the slice that drives edge status and path animation (trigger/updating/paused/error sets).
+  - **NodeDisplayStatus** – `'initial' | 'loading' | 'success' | 'error'` for node UI; **getNodeDisplayStatus({ loading, error, hasContent })**.
+  - **StoredGraphState** – shape for save/load (version + nodes + edges).
+- **FlowContext**: Module doc splits value into (1) Graph state, (2) Connection path state, (3) UI state. Same flat props, clearer sections.
+- **useGraphStateWithHistory**: JSDoc explains history (past/future), setNodes vs setNodesSilent, setStateImmediate.
+- **recollectionGraphStorage**: Uses **StoredGraphState** from state.ts; re-exports type. Doc references state flow.
+- **useRenderingNodeState**: Returns **displayStatus** (for NodeStatusIndicator/empty/error UI) and **lifecycle** (updating/error/paused for useSyncConnectionStatus). Hook calls useSyncConnectionStatus(id, state.lifecycle). Type includes RenderingNodeLifecycle.
+- **RenderingNode**: Uses **state.displayStatus** for NodeStatusIndicator instead of computing status locally.
+- **nodeLifecycle** and **connectionStatus**: Docs reference state.ts for overall state flow.
+
+## Design patterns in use
+
+| Pattern        | Where                                      |
+|----------------|--------------------------------------------|
+| **Registry**   | nodeRegistry, sourceRenderingLogic         |
+| **Builder**    | nodeTypeBuilder (descriptor per node type) |
+| **Pipeline**   | Resolve → Render → Display (rendering.ts)   |
+| **Strategy**   | Source logic per node type; output menu per descriptor |
+| **Shared helpers** | templateRefs, outputMenuHandlers, renderingUtils |
+
+## Suggested next steps
+
+- **CanvasPage**: Optional further split (e.g. move connection validation or node/edge change handlers into a hook) if the file grows again.

frontend/docs/QUICKSTART_FOR_JUNIORS.md

@@ -0,0 +1,99 @@
+# Junior Developer Quickstart
+
+## 1. Overview
+
+This guide explains how to set up the development environment, run the application, and make your first contribution.
+
+## 2. Prerequisites
+
+- **Node.js** (v18 or later)
+- **pnpm** (package manager)
+- **Docker** (for backend services, optional)
+- **Git** (version control)
+
+## 3. Repository Setup
+
+```bash
+# Clone the repository
+git clone https://github.com/your-org/zui.git
+cd zui
+
+# Install dependencies
+pnpm install
+```
+
+## 4. Running the Application
+
+### Frontend
+
+```bash
+pnpm dev
+```
+
+Open <http://localhost:3000> to see the app.
+
+### Backend
+
+```bash
+pnpm start
+```
+
+The backend API will be available at <http://localhost:5000>.
+
+## 5. Making Your First Contribution
+
+1. **Create a feature branch**:
+
+   ```bash
+   git checkout -b feat/your-first-contribution
+   ```
+
+2. **Make a small change**:
+   - Improve a README typo.
+   - Add a missing JSDoc comment.
+   - Fix a minor bug.
+3. **Run the appropriate tests** to ensure your change doesn't break anything:
+
+   ```bash
+   pnpm test
+   ```
+
+4. **Commit your changes** with a clear message:
+
+   ```bash
+   git commit -am "feat: brief description of change"
+   ```
+
+5. **Push the branch** to GitHub:
+
+   ```bash
+   git push origin feat/your-first-contribution
+   ```
+
+6. **Open a Pull Request** on GitHub, linking the relevant issue.
+
+## 6. Coding Standards
+
+- Follow the patterns in **ARCHITECTURE.md** and **CONTRIBUTING.md**.
+- Use TypeScript with strict mode.
+- Add JSDoc for all public APIs.
+- Keep changes small and focused.
+
+## 7. Helpful Links
+
+- **ARCHITECTURE.md** - High-level architecture overview.
+- **PERFORMANCE_IMPROVEMENTS.md** - Performance improvement plan.
+- **CODE_REVIEW_CHECKLIST.md** - Checklist for reviewers.
+
+## 8. FAQ
+
+**Q:** Do I need to write tests?  
+**A:** For bug fixes and new features, yes. Unit tests and integration tests are located under `frontend/src/app/**/*.test.tsx`.
+
+**Q:** How do I run the linter?  
+**A:** `pnpm lint`.
+
+**Q:** Where can I find more documentation?  
+**A:** See the `docs/` directory and the repository wiki.
+
+---\n*Happy coding!*

frontend/index.html

@@ -0,0 +1,16 @@
+<!doctype html>
+<html>
+
+<head>
+  <meta charset="utf-8" />
+  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+  <link rel="icon" href="/app-icon.svg" type="image/svg+xml" />
+  <title>ZOË | Kosmos</title>
+</head>
+
+<body>
+  <div id="root"></div>
+  <script type="module" src="/src/main.tsx"></script>
+</body>
+
+</html>

frontend/nginx.conf

@@ -0,0 +1,19 @@
+# Serve SPA and proxy /api to backend (Docker Compose).
+server {
+    listen 80;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    location /api/ {
+        proxy_pass http://backend:8080/api/;
+        proxy_http_version 1.1;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}

frontend/package.json

@@ -0,0 +1,69 @@
+{
+  "name": "reactflow-shadcn-app",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview",
+    "test": "vitest",
+    "test:run": "vitest run"
+  },
+  "dependencies": {
+    "@blocknote/core": "0.36.1",
+    "@blocknote/react": "0.36.1",
+    "@blocknote/shadcn": "0.36.1",
+    "@radix-ui/react-avatar": "^1.1.11",
+    "@radix-ui/react-collapsible": "^1.1.12",
+    "@radix-ui/react-context-menu": "^2.2.16",
+    "@radix-ui/react-dialog": "^1.1.15",
+    "@radix-ui/react-dropdown-menu": "^2.1.16",
+    "@radix-ui/react-menubar": "^1.1.16",
+    "@radix-ui/react-popover": "^1.1.15",
+    "@radix-ui/react-select": "^2.2.6",
+    "@radix-ui/react-separator": "^1.1.8",
+    "@radix-ui/react-slot": "^1.2.4",
+    "@radix-ui/react-switch": "^1.2.6",
+    "@radix-ui/react-toggle": "^1.1.10",
+    "@radix-ui/react-toggle-group": "^1.1.11",
+    "@radix-ui/react-tooltip": "^1.2.8",
+    "@tanstack/react-table": "^8.21.3",
+    "@types/prismjs": "^1.26.6",
+    "@wireweave/core": "^2.6.0",
+    "@xyflow/react": "^12.10.1",
+    "class-variance-authority": "^0.7.1",
+    "clsx": "^2.1.1",
+    "graphology": "^0.26.0",
+    "graphology-traversal": "^0.3.1",
+    "lucide-react": "^0.577.0",
+    "markdown-to-jsx": "^9.7.9",
+    "marked": "^17.0.4",
+    "next-themes": "^0.4.6",
+    "nunjucks": "^3.2.4",
+    "prism-react-renderer": "^2.4.1",
+    "prismjs": "^1.30.0",
+    "react": "18.2.0",
+    "react-arborist": "^3.4.3",
+    "react-dom": "18.2.0",
+    "react-router-dom": "^6.28.0",
+    "react-simple-code-editor": "^0.14.1",
+    "sonner": "^2.0.7",
+    "tailwind-merge": "^3.5.0",
+    "tailwindcss-animate": "^1.0.7",
+    "zustand": "^5.0.2"
+  },
+  "devDependencies": {
+    "@testing-library/react": "^16.0.0",
+    "@types/node": "^25.3.3",
+    "@types/react": "^18.0.0",
+    "@types/react-dom": "^18.0.0",
+    "@vitejs/plugin-react": "^5.1.4",
+    "autoprefixer": "^10.4.0",
+    "postcss": "^8.4.0",
+    "shadcn": "^4.0.0",
+    "tailwindcss": "^3.4.0",
+    "typescript": "^5.0.0",
+    "vite": "^7.3.1",
+    "vitest": "^2.1.6"
+  }
+}

frontend/src/app/NotFoundPage.tsx

@@ -0,0 +1,21 @@
+/**
+ * 404 page for unknown routes. Shown when no route matches.
+ */
+
+import React from 'react'
+import { Link } from 'react-router-dom'
+import { Button } from '@/components/ui/button'
+
+export function NotFoundPage() {
+  return (
+    <div className="flex min-h-dvh flex-col items-center justify-center gap-6 bg-background p-8">
+      <h1 className="text-2xl font-semibold text-foreground">Page not found</h1>
+      <p className="text-sm text-muted-foreground">
+        The page you’re looking for doesn’t exist or has been moved.
+      </p>
+      <Button asChild variant="default">
+        <Link to="/recollections">Back to Recollections</Link>
+      </Button>
+    </div>
+  )
+}

frontend/src/app/canvas/CanvasContextMenuContent.tsx

@@ -0,0 +1,62 @@
+/**
+ * Context menu content for the canvas: Create Node (grouped by classification) and Paste.
+ * Used inside CanvasPage so the menu structure lives in one place.
+ */
+
+import React from 'react'
+import {
+  ContextMenuContent,
+  ContextMenuItem,
+  ContextMenuGroup,
+  ContextMenuLabel,
+  ContextMenuSeparator,
+  ContextMenuSub,
+  ContextMenuSubContent,
+  ContextMenuSubTrigger,
+} from '@/components/ui/context-menu'
+import { ClipboardPaste } from 'lucide-react'
+import { getRegisteredNodeTypesGroupedByClassification } from '@/lib/graph/nodeRegistry'
+
+export type CanvasContextMenuContentProps = {
+  onCreateNode: (type: string) => void
+  onPaste: () => void
+}
+
+export function CanvasContextMenuContent({ onCreateNode, onPaste }: CanvasContextMenuContentProps) {
+  const groups = getRegisteredNodeTypesGroupedByClassification()
+  return (
+    <ContextMenuContent className="w-48" aria-label="Canvas menu: create node or paste">
+      <ContextMenuGroup>
+        <ContextMenuSub>
+          <ContextMenuSubTrigger>Create Node</ContextMenuSubTrigger>
+          <ContextMenuSubContent className="w-44">
+            {groups.map(
+              (group, groupIndex) =>
+                group.types.length > 0 && (
+                  <React.Fragment key={group.classification}>
+                    {groupIndex > 0 && <ContextMenuSeparator />}
+                    <ContextMenuGroup>
+                      <ContextMenuLabel className="text-muted-foreground">
+                        {group.label}
+                      </ContextMenuLabel>
+                      {group.types.map((desc) => (
+                        <ContextMenuItem key={desc.id} onSelect={() => onCreateNode(desc.id)}>
+                          {desc.menuIcon}
+                          {desc.menuLabel}
+                        </ContextMenuItem>
+                      ))}
+                    </ContextMenuGroup>
+                  </React.Fragment>
+                )
+            )}
+          </ContextMenuSubContent>
+        </ContextMenuSub>
+        <ContextMenuSeparator />
+        <ContextMenuItem onSelect={onPaste}>
+          <ClipboardPaste className="mr-2 h-4 w-4" />
+          Paste
+        </ContextMenuItem>
+      </ContextMenuGroup>
+    </ContextMenuContent>
+  )
+}

frontend/src/app/canvas/CanvasPage.tsx

@@ -0,0 +1,813 @@
+/**
+ * Canvas page: the graph editor (React Flow) with nodes, edges, context menu, import/export.
+ * Rendered inside the platform when a recollection is selected.
+ */
+
+import React, { useCallback, useEffect, useMemo, useRef } from 'react'
+import {
+  ReactFlow,
+  ReactFlowProvider,
+  Controls,
+  Background,
+  MiniMap,
+  addEdge,
+  applyNodeChanges,
+  applyEdgeChanges,
+  useNodesInitialized,
+  useReactFlow,
+  type Node,
+  type Edge,
+  type Connection,
+  type ColorMode,
+  type NodeChange,
+  type EdgeChange,
+} from '@xyflow/react'
+import { AnimatedEdge } from '@/components/graph/AnimatedEdge'
+import {
+  GraphContext,
+  ConnectionPathContext,
+  FlowUIContext,
+} from '@/lib/graph/flowContext'
+import { useTheme } from '@/lib/themeContext'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import { useCanvasGraph } from '@/app/canvas/useCanvasGraph'
+import { getExampleGraph, backfillEdgeTargetTypes } from '@/app/canvas/canvasGraphUtils'
+import { ContextMenu, ContextMenuTrigger } from '@/components/ui/context-menu'
+import { CanvasContextMenuContent } from '@/app/canvas/CanvasContextMenuContent'
+import { useCanvasConnectionPathFromStore } from '@/app/canvas/useCanvasConnectionPathFromStore'
+import { dispatchCanvasCommand } from '@/app/canvas/canvasStore'
+import { useRecollectionActions } from '@/app/recollections/layout/RecollectionActionsContext'
+import type { StoredGraphState } from '@/app/recollections/state/recollectionStore'
+import { createContextualNode } from '@/app/canvas/ContextualZoomNode'
+import { ViewportDisplayProvider } from '@/app/canvas/ViewportDisplayContext'
+import { FlowKeyboardShortcuts } from '@/components/graph/FlowKeyboardShortcuts'
+import {
+  Empty,
+  EmptyContent,
+  EmptyDescription,
+  EmptyHeader,
+  EmptyMedia,
+  EmptyTitle,
+} from '@/components/ui/empty'
+import { Button } from '@/components/ui/button'
+import {
+  Dialog,
+  DialogContent,
+  DialogTitle,
+} from '@/components/ui/dialog'
+import { FolderOpen, FileStack, CircleDotDashed } from 'lucide-react'
+import { getDefaultDataForType, getNextNodeId } from '@/lib/graph/flowUtils'
+import {
+  getRegisteredNodeTypes,
+  getRegisteredNodeTypeIds,
+  getDefaultStyle,
+  getNodeType,
+  getConnectionLabelForTarget,
+  isConnectionAllowed,
+} from '@/lib/graph/nodeRegistry'
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+import { toast } from 'sonner'
+import { RECOLLECTION_VERSION } from '@/app/recollections/state/recollectionGraphStorage'
+
+const SNAP_GRID: [number, number] = [15, 15]
+const DUPLICATE_OFFSET = { x: 30, y: 30 }
+const snapToGrid = (x: number, y: number): { x: number; y: number } => ({
+  x: Math.round(x / SNAP_GRID[0]) * SNAP_GRID[0],
+  y: Math.round(y / SNAP_GRID[1]) * SNAP_GRID[1],
+})
+
+function FlowFitViewOnLoad({ disabled }: { disabled?: boolean }) {
+  const nodesInitialized = useNodesInitialized()
+  const { fitView } = useReactFlow()
+  React.useEffect(() => {
+    if (disabled || !nodesInitialized) return
+    fitView?.({ duration: 200 })
+  }, [disabled, nodesInitialized, fitView])
+  return null
+}
+
+function FocusNodeOnLoad({ focusNodeId }: { focusNodeId?: string }) {
+  const nodesInitialized = useNodesInitialized()
+  const { getNodes, setCenter, screenToFlowPosition, project } = useReactFlow()
+
+  React.useEffect(() => {
+    if (!focusNodeId || !nodesInitialized) return
+    // Small delay so node DOM and layout are fully ready before centering/zooming.
+    const timer = setTimeout(() => {
+      const nodes = getNodes()
+      const node = nodes.find((n) => n.id === focusNodeId)
+      if (!node) return
+
+      const el = document.querySelector(
+        `.react-flow__node[data-id="${focusNodeId}"]`
+      ) as HTMLElement | null
+
+      if (el) {
+        const rect = el.getBoundingClientRect()
+        const screenCenter = { x: rect.left + rect.width / 2, y: rect.top + rect.height / 2 }
+        const toFlow = screenToFlowPosition ?? project
+        if (toFlow) {
+          const flowCenter = toFlow(screenCenter)
+          setCenter(flowCenter.x, flowCenter.y, { duration: 400, zoom: 1.8 })
+          return
+        }
+      }
+
+      // Fallback: center using node position + dimensions from React Flow state.
+      const anyNode = node as Node & {
+        positionAbsolute?: { x: number; y: number }
+        width?: number
+        height?: number
+      }
+      const basePos = anyNode.positionAbsolute ?? anyNode.position ?? { x: 0, y: 0 }
+      const width = anyNode.width ?? 0
+      const height = anyNode.height ?? 0
+      const centerX = basePos.x + width / 2
+      const centerY = basePos.y + height / 2
+      setCenter(centerX, centerY, { duration: 400, zoom: 1.8 })
+    }, 150)
+
+    return () => clearTimeout(timer)
+  }, [focusNodeId, nodesInitialized, getNodes, setCenter, screenToFlowPosition, project])
+
+  return null
+}
+
+type FullscreenNodeOverlayProps = {
+  nodeId: string
+  nodes: AppNode[]
+  onClose: () => void
+}
+
+function FullscreenNodeOverlay({ nodeId, nodes, onClose }: FullscreenNodeOverlayProps) {
+  const open = nodeId != null
+  const node = nodes.find((n) => n.id === nodeId)
+  if (!nodeId) return null
+
+  return (
+    <Dialog open={open} onOpenChange={(isOpen) => { if (!isOpen) onClose() }}>
+      <DialogContent
+        className="max-w-[94vw] w-[94vw] max-h-[90vh] h-[90vh] p-0 gap-0 overflow-hidden flex flex-col border rounded-lg shadow-xl bg-card"
+        aria-describedby={undefined}
+        hideCloseButton
+      >
+        <DialogTitle className="sr-only">Node: {node?.id ?? nodeId}</DialogTitle>
+        {node && node.type && (
+          <FullscreenNodeContent node={node} />
+        )}
+      </DialogContent>
+    </Dialog>
+  )
+}
+
+function FullscreenNodeContent({ node }: { node: AppNode }) {
+  const descriptor = getNodeType(node.type ?? '')
+  const NodeComponent = descriptor?.component as React.ComponentType<{
+    id: string
+    data: Record<string, unknown>
+    type?: string
+    selected?: boolean
+    width?: number
+    height?: number
+  }> | undefined
+  if (!NodeComponent) return null
+
+  const w = typeof window !== 'undefined' ? Math.round(window.innerWidth * 0.94) : 1200
+  const h = typeof window !== 'undefined' ? Math.round(window.innerHeight * 0.9) : 800
+
+  const fullscreenNodeForStore: AppNode = {
+    ...node,
+    position: node.position ?? { x: 0, y: 0 },
+    style: { ...(node.style as object), width: w, height: h },
+  }
+
+  return (
+    <div className="flex-1 min-h-0 overflow-hidden flex">
+      <ReactFlowProvider initialNodes={[fullscreenNodeForStore]} initialEdges={[]}>
+        <NodeComponent
+          id={node.id}
+          data={(node.data as Record<string, unknown>) ?? {}}
+          type={node.type}
+          selected={false}
+          width={w}
+          height={h}
+        />
+      </ReactFlowProvider>
+    </div>
+  )
+}
+
+export type CanvasPageProps = {
+  /** Optional recollection id for per-recollection graph loading */
+  recollectionId?: string
+  /** Optional node id to focus when the canvas loads (e.g. from Katalogos artifacts). */
+  focusNodeId?: string
+}
+
+export function CanvasPage({ recollectionId, focusNodeId }: CanvasPageProps) {
+  const { theme } = useTheme()
+  const { showMinimap } = usePlatform()
+  const {
+    nodes,
+    edges,
+    setNodes,
+    setEdges,
+    setNodesSilent,
+    applyGraph,
+    saveForDragEnd,
+    commitDragEnd,
+    undo,
+    redo,
+    canUndo,
+    canRedo,
+    setStateImmediate,
+    save,
+    saveStatus,
+  } = useCanvasGraph(recollectionId)
+
+  const [rfInstance, setRfInstance] = React.useState<unknown>(null)
+  const [renamingNodeId, setRenamingNodeId] = React.useState<string | null>(null)
+  const [connectionFrom, setConnectionFrom] = React.useState<{ nodeId: string; sourceHandle?: string } | null>(null)
+  const wrapperRef = useRef<HTMLDivElement | null>(null)
+  const canvasWrapperRef = useRef<HTMLDivElement | null>(null)
+  const lastClickRef = useRef<{ clientX: number; clientY: number } | null>(null)
+  const flowActionsRef = useRef<{ pasteAtViewportCenter: () => void; fitView: () => void } | null>(null)
+  const [contextTarget, setContextTarget] = React.useState<null | { type: 'canvas'; clientX: number; clientY: number }>(null)
+  const [lastCreatedNodeId, setLastCreatedNodeId] = React.useState<string | null>(null)
+  const [isPanning, setIsPanning] = React.useState(false)
+  const [isSelecting, setIsSelecting] = React.useState(false)
+  const [ariaAnnouncement, setAriaAnnouncement] = React.useState<string | null>(null)
+  const [fullscreenNodeId, setFullscreenNodeId] = React.useState<string | null>(null)
+
+  const graphApplyTimeoutRef = React.useRef<ReturnType<typeof setTimeout> | null>(null)
+  const GRAPH_APPLY_DEBOUNCE_MS = 300
+  useEffect(() => {
+    if (graphApplyTimeoutRef.current) clearTimeout(graphApplyTimeoutRef.current)
+    graphApplyTimeoutRef.current = setTimeout(() => {
+      graphApplyTimeoutRef.current = null
+      dispatchCanvasCommand({ type: 'graph/apply', payload: { nodes, edges } })
+    }, GRAPH_APPLY_DEBOUNCE_MS)
+    return () => {
+      if (graphApplyTimeoutRef.current) {
+        clearTimeout(graphApplyTimeoutRef.current)
+        graphApplyTimeoutRef.current = null
+      }
+    }
+  }, [nodes, edges])
+
+  const connectionPath = useCanvasConnectionPathFromStore()
+
+  const nodesRef = useRef(nodes)
+  nodesRef.current = nodes
+  const graphRef = useRef<{ nodes: AppNode[]; edges: AppEdge[] }>({ nodes: [], edges: [] })
+  graphRef.current.nodes = nodes
+  graphRef.current.edges = edges
+
+  const pendingChangesRef = useRef<NodeChange<Node>[]>([])
+  const rafRef = useRef<number | null>(null)
+  const onNodesChange = useCallback(
+    (changes: NodeChange<Node>[]) => {
+      if (changes.length === 0) return
+      const pending = pendingChangesRef.current
+      for (const c of changes) {
+        const id = (c as { id?: string }).id
+        if (id != null) {
+          const i = pending.findIndex((p) => (p as { id?: string }).id === id)
+          if (i >= 0) pending[i] = c
+          else pending.push(c)
+        } else pending.push(c)
+      }
+      if (rafRef.current === null) {
+        rafRef.current = requestAnimationFrame(() => {
+          rafRef.current = null
+          const toApply = pendingChangesRef.current.splice(0, pendingChangesRef.current.length)
+          if (toApply.length === 0) return
+          setNodesSilent((nds) => {
+            // Drop dimension-only changes that don't change the node (e.g. React Flow re-reporting on visibility).
+            // Avoids graph/apply and store churn when nodes become visible with onlyRenderVisibleElements.
+            const filtered = toApply.filter((c) => {
+              const ch = c as NodeChange<Node> & { type?: string; dimensions?: { width?: number; height?: number } }
+              if (ch.type !== 'dimensions' || ch.dimensions == null) return true
+              const node = nds.find((n) => n.id === (ch as { id?: string }).id)
+              if (!node) return true
+              const nw = (node as Node & { width?: number }).width
+              const nh = (node as Node & { height?: number }).height
+              return nw !== ch.dimensions.width || nh !== ch.dimensions.height
+            })
+            if (filtered.length === 0) return nds
+            return applyNodeChanges(filtered, nds)
+          })
+        })
+      }
+    },
+    [setNodesSilent]
+  )
+
+  const nodeTypes = useMemo(
+    () =>
+      Object.fromEntries(
+        getRegisteredNodeTypes().map((r) => [r.id, createContextualNode(r.component)])
+      ),
+    []
+  )
+  const edgeTypes = useMemo(() => ({ animated: AnimatedEdge }), [])
+  const defaultEdgeOptions = useMemo(() => ({ type: 'animated' as const }), [])
+
+  const onEdgesChange = useCallback(
+    (changes: EdgeChange<Edge>[]) => {
+      if (changes.length === 0) return
+      setEdges((eds) => applyEdgeChanges(changes, eds))
+    },
+    [setEdges]
+  )
+
+  const onConnect = useCallback(
+    (params: Connection) => {
+      const targetType =
+        nodesRef.current.find((n) => n.id === params.target)?.type ?? ''
+      const conn = { ...params, data: { targetType } as Record<string, unknown> }
+      setEdges((eds) => addEdge(conn, eds))
+    },
+    [setEdges]
+  )
+
+  const isValidConnection = useCallback((connection: Connection | AppEdge) => {
+    const src = 'source' in connection ? connection.source : undefined
+    const tgt = 'target' in connection ? connection.target : undefined
+    if (typeof src !== 'string' || typeof tgt !== 'string') return false
+    const currentNodes = nodesRef.current
+    const sourceNode = currentNodes.find((n) => n.id === src)
+    const targetNode = currentNodes.find((n) => n.id === tgt)
+    const sourceType = sourceNode?.type
+    const targetType = targetNode?.type
+    if (!sourceType || !targetType) return false
+    if (sourceType === 'render' && targetType === 'config') {
+      const targetData = targetNode?.data as { configType?: string } | undefined
+      if (targetData?.configType !== 'markdown') return false
+    }
+    return isConnectionAllowed(sourceType, targetType, src, tgt)
+  }, [])
+
+  const onConnectStart = useCallback(
+    (
+      _: React.MouseEvent<Element> | React.TouchEvent<Element> | MouseEvent | TouchEvent,
+      params: { nodeId?: string | null; handleId?: string | null; handleType?: string | null }
+    ) => {
+      if (params.handleType !== 'source' || !params.nodeId) {
+        setConnectionFrom(null)
+        return
+      }
+      setConnectionFrom({ nodeId: params.nodeId, sourceHandle: params.handleId ?? undefined })
+    },
+    []
+  )
+  const onConnectEnd = useCallback(() => setConnectionFrom(null), [])
+
+  const onInit = useCallback((instance: unknown) => setRfInstance(instance), [])
+
+  const onMoveStart = useCallback(() => setIsPanning(true), [])
+  const onMoveEnd = useCallback(() => setIsPanning(false), [])
+  const onSelectionDragStart = useCallback(() => setIsSelecting(true), [])
+  const onSelectionDragStop = useCallback(() => setIsSelecting(false), [])
+
+  const onNodeDragStart = useCallback(() => saveForDragEnd(), [saveForDragEnd])
+  const onNodeDragStop = useCallback(() => commitDragEnd(), [commitDragEnd])
+
+  const handleLoadExample = useCallback(() => {
+    const { nodes: exampleNodes, edges: exampleEdges } = getExampleGraph()
+    setStateImmediate({ nodes: exampleNodes, edges: exampleEdges })
+    toast.success('Example loaded')
+  }, [setStateImmediate])
+
+  const selectedNodes = useMemo(
+    () => nodes.filter((n) => (n as Node & { selected?: boolean }).selected),
+    [nodes]
+  )
+
+  const handleDuplicate = useCallback(() => {
+    if (selectedNodes.length === 0 || !setNodes) return
+    setNodes((nds: Node[]) => {
+      const existingIds = nds.map((n) => n.id)
+      const toAdd: Node[] = []
+      for (const node of selectedNodes) {
+        const n = node as Node & { selected?: boolean }
+        const pos = n.position ?? { x: 0, y: 0 }
+        const newId = getNextNodeId(String(n.type), [...existingIds, ...toAdd.map((x) => x.id)])
+        existingIds.push(newId)
+        const newNode: Node = {
+          id: newId,
+          type: n.type,
+          position: { x: pos.x + DUPLICATE_OFFSET.x, y: pos.y + DUPLICATE_OFFSET.y },
+          data: typeof n.data === 'object' && n.data !== null ? { ...(n.data as object) } : n.data,
+          style: getDefaultStyle(String(n.type)),
+        }
+        if (
+          newNode.data &&
+          typeof newNode.data === 'object' &&
+          'title' in newNode.data &&
+          String(n.type) === 'config'
+        ) {
+          ; (newNode.data as Record<string, unknown>).title = `${newId}`
+        }
+        toAdd.push(newNode)
+      }
+      return nds.concat(toAdd)
+    })
+  }, [selectedNodes, setNodes])
+
+  const handleCopy = useCallback(() => {
+    if (selectedNodes.length !== 1) return
+    const node = selectedNodes[0] as Node & { selected?: boolean }
+    const copy = {
+      id: node.id,
+      type: node.type,
+      data: node.data,
+      position: node.position,
+      style: node.style,
+    }
+    navigator.clipboard?.writeText(JSON.stringify(copy)).catch(() => { })
+  }, [selectedNodes])
+
+  const handlePaste = useCallback(() => {
+    flowActionsRef.current?.pasteAtViewportCenter?.()
+  }, [])
+
+  const { setFluxSlot, onImport } = useRecollectionActions()
+
+  const onRefreshFromStore = useCallback(
+    (graph: StoredGraphState) => {
+      const nodes = graph.nodes as AppNode[]
+      const edges = backfillEdgeTargetTypes(nodes, graph.edges as AppEdge[])
+      setStateImmediate({ nodes, edges })
+    },
+    [setStateImmediate]
+  )
+
+  useEffect(() => {
+    const slot = {
+      saveStatus,
+      onSave: recollectionId
+        ? () => {
+            save()
+            toast.success('Saved')
+          }
+        : () => {},
+      canSave: Boolean(recollectionId),
+      undo,
+      redo,
+      canUndo,
+      canRedo,
+      onRefreshFromStore,
+      onDuplicate: handleDuplicate,
+      onCopy: handleCopy,
+      onPaste: handlePaste,
+      canDuplicate: selectedNodes.length > 0,
+      canCopy: selectedNodes.length === 1,
+      onFitView: () => flowActionsRef.current?.fitView?.(),
+    }
+    setFluxSlot(slot)
+    return () => setFluxSlot(null)
+  }, [
+    setFluxSlot,
+    saveStatus,
+    recollectionId,
+    save,
+    undo,
+    redo,
+    canUndo,
+    canRedo,
+    onRefreshFromStore,
+    handleDuplicate,
+    handleCopy,
+    handlePaste,
+    selectedNodes.length,
+  ])
+
+  const graphContextValue = useMemo(
+    () => ({ setNodes, setEdges, graphRef, edges }),
+    [setNodes, setEdges, edges]
+  )
+  const connectionPathContextValue = useMemo(
+    () => ({
+      connectionPathUpdatingNodeIds: connectionPath.connectionPathUpdatingNodeIds,
+      connectionPathTriggerNodeIds: connectionPath.connectionPathTriggerNodeIds,
+      addConnectionPathTrigger: connectionPath.addConnectionPathTrigger,
+      connectionPathNodeIds: connectionPath.connectionPathNodeIds,
+      connectionPathPausedSegmentNodeIds: connectionPath.connectionPathPausedSegmentNodeIds,
+      connectionPathActiveSegmentNodeIds: connectionPath.connectionPathActiveSegmentNodeIds,
+      connectionPathPausedNodeIds: connectionPath.connectionPathPausedNodeIds,
+      addConnectionPathPausedNode: connectionPath.addConnectionPathPausedNode,
+      removeConnectionPathPausedNode: connectionPath.removeConnectionPathPausedNode,
+      connectionPathErrorNodeIds: connectionPath.connectionPathErrorNodeIds,
+      addConnectionPathError: connectionPath.addConnectionPathError,
+      removeConnectionPathError: connectionPath.removeConnectionPathError,
+      startConnectionPathUpdate: connectionPath.startConnectionPathUpdate,
+      endConnectionPathUpdate: connectionPath.endConnectionPathUpdate,
+    }),
+    [connectionPath]
+  )
+  const flowUIContextValue = useMemo(
+    () => ({
+      renamingNodeId,
+      setRenamingNodeId,
+      connectionFrom,
+      setConnectionFrom,
+      isValidConnection,
+      flowActionsRef,
+      fullscreenNodeId,
+      setFullscreenNodeId,
+    }),
+    [
+      renamingNodeId,
+      setRenamingNodeId,
+      connectionFrom,
+      setConnectionFrom,
+      isValidConnection,
+      flowActionsRef,
+      fullscreenNodeId,
+      setFullscreenNodeId,
+    ]
+  )
+
+  const prevNodesRef = useRef<AppNode[]>([])
+  const prevNodesForFlowRef = useRef<Node[]>([])
+  const nodesForFlow = useMemo(() => {
+    const prev = prevNodesRef.current
+    if (nodes === prev) return prevNodesForFlowRef.current
+    const prevById = new Map(prev.map((n) => [n.id, n]))
+    const prevWrappedById = new Map(
+      prevNodesForFlowRef.current.map((w, i) => [prev[i]?.id, w])
+    )
+    const result = nodes.map((n) => {
+      const prevNode = prevById.get(n.id)
+      if (prevNode === n && prevWrappedById.has(n.id)) {
+        return prevWrappedById.get(n.id)!
+      }
+      return {
+        ...n,
+        className: [n.className, 'nowheel'].filter(Boolean).join(' '),
+      }
+    })
+    prevNodesRef.current = nodes
+    prevNodesForFlowRef.current = result
+    return result
+  }, [nodes])
+  const edgesForFlow = useMemo(
+    () =>
+      edges.map((e) => {
+        const targetType =
+          (typeof e.data === 'object' && e.data !== null && (e.data as Record<string, unknown>).targetType != null
+            ? (e.data as Record<string, unknown>).targetType
+            : '') as string
+        const connectionLabel = getConnectionLabelForTarget(targetType)
+        const baseData =
+          typeof e.data === 'object' && e.data !== null ? (e.data as Record<string, unknown>) : {}
+        return {
+          ...e,
+          data: { ...baseData, connectionLabel },
+        }
+      }),
+    [edges]
+  )
+
+  const onContextMenuCapture = useCallback((ev: React.MouseEvent) => {
+    const target = ev.target as HTMLElement
+    if (target.closest('.react-flow__node')) {
+      ev.preventDefault()
+      ev.stopPropagation()
+    }
+  }, [])
+
+  const onCanvasContextMenu = useCallback((ev: React.MouseEvent) => {
+    ev.preventDefault()
+    lastClickRef.current = { clientX: ev.clientX, clientY: ev.clientY }
+    setContextTarget({ type: 'canvas', clientX: ev.clientX, clientY: ev.clientY })
+  }, [])
+
+  const getMenuPosition = useCallback(() => {
+    if (!rfInstance) return null
+    const click = contextTarget ?? lastClickRef.current
+    const clientX = click?.clientX ?? window.innerWidth / 2
+    const clientY = click?.clientY ?? window.innerHeight / 2
+    try {
+      type ScreenToFlow = (p: { x: number; y: number }) => { x: number; y: number }
+      const inst = rfInstance as { screenToFlowPosition?: ScreenToFlow; [k: string]: unknown }
+      const screenToFlow = inst.screenToFlowPosition ?? (inst['project'] as ScreenToFlow | undefined)
+      const p = screenToFlow?.call(rfInstance, { x: clientX, y: clientY })
+      return p ? snapToGrid(p.x, p.y) : null
+    } catch {
+      return snapToGrid(clientX, clientY)
+    }
+  }, [rfInstance, contextTarget])
+
+  const createNode = useCallback(
+    (type: string) => {
+      const position = getMenuPosition()
+      if (position == null || typeof type !== 'string') return
+      const existingIds = nodesRef.current.map((n) => n.id).filter((id): id is string => id != null)
+      const newId = getNextNodeId(type, existingIds)
+      const dataMap = getDefaultDataForType(type, newId)
+      const style = getDefaultStyle(type)
+      const newNode: Node = {
+        id: newId,
+        type: type as Node['type'],
+        position: { x: position.x, y: position.y },
+        data: dataMap,
+        style,
+      }
+      setNodes((nds) => nds.concat(newNode))
+      setLastCreatedNodeId(newId)
+      lastClickRef.current = null
+      setContextTarget(null)
+    },
+    [getMenuPosition, setNodes]
+  )
+
+  React.useEffect(() => {
+    if (lastCreatedNodeId == null) return
+    const id = lastCreatedNodeId
+    const raf = requestAnimationFrame(() => {
+      const nodeEl = document.querySelector(`.react-flow__node[data-id="${id}"]`) as HTMLElement | null
+      if (nodeEl) {
+        setAriaAnnouncement('Node created')
+        nodeEl.setAttribute('tabindex', '-1')
+        nodeEl.focus({ preventScroll: false })
+        setTimeout(() => setAriaAnnouncement(null), 1000)
+      }
+      setLastCreatedNodeId(null)
+    })
+    return () => cancelAnimationFrame(raf)
+  }, [lastCreatedNodeId, nodes])
+
+  const pasteNode = useCallback(async () => {
+    const position = getMenuPosition()
+    if (position == null) return
+    try {
+      const text = await navigator.clipboard?.readText()
+      if (!text) return
+      const raw = JSON.parse(text) as { id?: string; type?: string; data?: Record<string, unknown>; position?: { x: number; y: number }; style?: unknown }
+      const validIds = getRegisteredNodeTypeIds()
+      if (!raw || typeof raw.type !== 'string' || !validIds.includes(raw.type)) return
+      const nodeType = raw.type
+      setNodes((nds) => {
+        const existingIds = nds.map((n) => n.id).filter((id): id is string => id != null)
+        const newId = getNextNodeId(nodeType, existingIds)
+        const data = raw.data != null && typeof raw.data === 'object' ? { ...raw.data } : {}
+        if (nodeType === 'config' && data && 'title' in data) data.title = `config-${newId}`
+        const style = getDefaultStyle(nodeType)
+        const newNode: Node = {
+          id: newId,
+          type: nodeType as Node['type'],
+          position: { x: position.x, y: position.y },
+          data,
+          style,
+        }
+        return nds.concat(newNode)
+      })
+      lastClickRef.current = null
+      setContextTarget(null)
+    } catch {
+      /* ignore */
+    }
+  }, [getMenuPosition, setNodes])
+
+  const deleteNode = useCallback(
+    (id: string | undefined) => {
+      if (!id) return
+      applyGraph(({ nodes: nds, edges: eds }) => ({
+        nodes: nds.filter((n) => n.id !== id),
+        edges: eds.filter((e) => e.source !== id && e.target !== id),
+      }))
+      setContextTarget(null)
+    },
+    [applyGraph]
+  )
+
+  return (
+    <div
+      className="reactflow-wrapper flex flex-col h-full"
+      ref={wrapperRef}
+      onContextMenuCapture={onContextMenuCapture}
+      onContextMenu={onCanvasContextMenu}
+      style={{ position: 'relative' }}
+    >
+      <div role="status" aria-live="polite" aria-atomic className="sr-only">
+        {ariaAnnouncement}
+      </div>
+      <div className="flex-1 min-h-0 relative flex flex-col">
+        <div className="flex-1 min-h-0 flex flex-col">
+          <GraphContext.Provider value={graphContextValue}>
+          <ConnectionPathContext.Provider value={connectionPathContextValue}>
+          <FlowUIContext.Provider value={flowUIContextValue}>
+            <ContextMenu>
+              <ContextMenuTrigger asChild>
+                <div
+                  ref={canvasWrapperRef}
+                  className="flex-1 min-h-0 w-full relative"
+                  role="application"
+                  aria-label="Graph canvas"
+                  tabIndex={0}
+                >
+                  {nodes.length === 0 && (
+                    <div className="absolute inset-0 flex items-center justify-center pointer-events-none z-10">
+                      <div className="pointer-events-auto rounded-lg border border-border bg-background/95 dark:bg-background/90 shadow-sm">
+                        <Empty className="p-6 md:p-8">
+                          <EmptyHeader>
+                            <EmptyMedia variant="icon">
+                              <CircleDotDashed className="size-6" />
+                            </EmptyMedia>
+                            <EmptyTitle>Start adding a new node!</EmptyTitle>
+                            <EmptyDescription>
+                              Right‑click to add nodes. <br />
+                              Import a recollection or paste a node.
+                            </EmptyDescription>
+                          </EmptyHeader>
+                          <EmptyContent className="flex-row flex-wrap justify-center gap-2">
+                            <Button onClick={onImport} variant="outline" size="sm">
+                              <FolderOpen className="size-4" />
+                              Import…
+                            </Button>
+                            <Button onClick={handleLoadExample} variant="outline" size="sm">
+                              <FileStack className="size-4" />
+                              Load example
+                            </Button>
+                          </EmptyContent>
+                        </Empty>
+                      </div>
+                    </div>
+                  )}
+                  <ReactFlowProvider initialNodes={nodes} initialEdges={edges} fitView>
+                    <ViewportDisplayProvider>
+                      <FlowFitViewOnLoad disabled={Boolean(focusNodeId)} />
+                      <FocusNodeOnLoad focusNodeId={focusNodeId} />
+                      <FlowKeyboardShortcuts />
+                      <ReactFlow
+                      className={isPanning ? 'react-flow--panning' : isSelecting ? 'react-flow--selecting' : undefined}
+                      nodes={nodesForFlow}
+                      edges={edgesForFlow}
+                      onNodesChange={onNodesChange}
+                      onEdgesChange={onEdgesChange}
+                      onConnect={onConnect}
+                      onConnectStart={onConnectStart}
+                      onConnectEnd={onConnectEnd}
+                      onNodeDragStart={onNodeDragStart}
+                      onNodeDragStop={onNodeDragStop}
+                      onMoveStart={onMoveStart}
+                      onMoveEnd={onMoveEnd}
+                      onSelectionDragStart={onSelectionDragStart}
+                      onSelectionDragStop={onSelectionDragStop}
+                      isValidConnection={isValidConnection}
+                      nodeTypes={nodeTypes}
+                      edgeTypes={edgeTypes}
+                      defaultEdgeOptions={defaultEdgeOptions}
+                      colorMode={theme as ColorMode}
+                      minZoom={0.1}
+                      maxZoom={2}
+                      snapToGrid
+                      snapGrid={SNAP_GRID}
+                      fitView
+                      onInit={onInit}
+                      nodeDragThreshold={1}
+                      onlyRenderVisibleElements
+                      nodeOrigin={[0, 0]}
+                      nodesDraggable
+                      nodesConnectable
+                      elementsSelectable
+                      panOnScroll
+                      zoomOnScroll
+                      zoomActivationKeyCode="Meta"
+                      panOnDrag={[1]}
+                      selectionOnDrag
+                    >
+                      {/* BackgroundVariant from @xyflow/system expects enum; 'dots' is valid at runtime */}
+                      <Background variant={'dots' as React.ComponentProps<typeof Background>['variant']} gap={20} />
+                      <div role="group" aria-label="Canvas controls: zoom and fit view">
+                        <Controls />
+                      </div>
+                      {showMinimap && nodes.length > 5 && (
+                        <div role="region" aria-label="Minimap: overview of the graph">
+                          <MiniMap />
+                        </div>
+                      )}
+                    </ReactFlow>
+                    </ViewportDisplayProvider>
+                  </ReactFlowProvider>
+                </div>
+              </ContextMenuTrigger>
+              <CanvasContextMenuContent onCreateNode={createNode} onPaste={pasteNode} />
+            </ContextMenu>
+            {fullscreenNodeId && (
+              <FullscreenNodeOverlay
+                nodeId={fullscreenNodeId}
+                nodes={nodes}
+                onClose={() => setFullscreenNodeId(null)}
+              />
+            )}
+          </FlowUIContext.Provider>
+          </ConnectionPathContext.Provider>
+          </GraphContext.Provider>
+        </div>
+      </div>
+    </div>
+  )
+}

frontend/src/app/canvas/ContextualZoomNode.tsx

@@ -0,0 +1,124 @@
+/**
+ * Contextual zoom: when zoomed out past a threshold, nodes render as compact
+ * icon-only views using each type's menuIcon from the node registry.
+ * @see https://reactflow.dev/examples/interaction/contextual-zoom
+ */
+
+import React, { useContext } from 'react'
+import { getNodeType, getDefaultStyle } from '@/lib/graph/nodeRegistry'
+import { ViewportDisplayContext } from '@/app/canvas/ViewportDisplayContext'
+import { InputHandle, OutputHandle } from '@/components/graph/NodeHandles'
+import { cn } from '@/lib/utils'
+
+const MIN_ZOOM = 0.1
+const MAX_ZOOM = 2
+/** When zoom <= this value, show compact icon view (bottom ~30% of zoom range). */
+export const CONTEXTUAL_ZOOM_THRESHOLD = MIN_ZOOM + 0.1 * (MAX_ZOOM - MIN_ZOOM)
+
+/** Handle id per type for compact view (input, output). */
+const COMPACT_HANDLES: Record<string, { input?: string; output?: string }> = {
+  config: { input: 'ain', output: 'out' },
+  render: { input: 'ain' },
+  variable: { output: 'out' },
+  function: { input: 'in', output: 'out' },
+  data: { output: 'out' },
+}
+
+type NodeProps = {
+  id: string
+  type?: string
+  data?: Record<string, unknown>
+  selected?: boolean
+  width?: number
+  height?: number
+  [key: string]: unknown
+}
+
+function CompactNodeView({ id, type, selected, width, height }: NodeProps) {
+  const descriptor = type ? getNodeType(type) : undefined
+  const icon = descriptor?.menuIcon ?? null
+  const handles = type ? COMPACT_HANDLES[type] ?? { output: 'out' } : {}
+  const defaultStyle = type ? getDefaultStyle(type) : { width: 320, height: 320 }
+  const w = width ?? defaultStyle.width
+  const h = height ?? defaultStyle.height
+
+  return (
+    <div
+      className={cn(
+        'flex flex-col rounded-md border bg-card text-card-foreground transition-[border-color,box-shadow] duration-200',
+        'border-input hover:ring-1',
+        selected &&
+        'border-primary/50 shadow-[0_0_0_2px_hsl(var(--primary)_/_0.15)] dark:border-primary/35 dark:shadow-[0_0_0_2px_hsl(var(--primary)_/_0.1)]'
+      )}
+      style={{
+        width: w,
+        height: h,
+        minWidth: w,
+        minHeight: h,
+      }}
+      data-selected={selected}
+    >
+      {handles.input && (
+        <InputHandle id={handles.input} nodeId={id} />
+      )}
+      <div className="flex flex-1 flex-col items-center justify-center gap-2 px-3 pb-3 pt-2">
+        <span className="flex shrink-0 items-center justify-center [&>svg]:h-14 [&>svg]:w-14" aria-hidden>
+          {icon}
+        </span>
+        <span className="truncate text-center text-lg font-medium text-foreground" title={id}>
+          {id}
+        </span>
+      </div>
+      {handles.output && (
+        <OutputHandle id={handles.output} />
+      )}
+    </div>
+  )
+}
+
+/**
+ * Wraps a node component so that when the viewport zoom is at or below
+ * CONTEXTUAL_ZOOM_THRESHOLD, the node renders as a compact icon-only view.
+ * Inner is always mounted (hidden when compact) so switching zoom does not
+ * remount and re-trigger effects (e.g. RenderingNode fetch).
+ */
+export function createContextualNode<P extends NodeProps>(
+  Inner: React.ComponentType<P>
+): React.ComponentType<P> {
+  function ContextualZoomNode(props: P) {
+    const displayMode = useContext(ViewportDisplayContext)
+    const showCompact = displayMode === 'compact'
+    const p = props as NodeProps
+    const type = p.type
+    const defaultStyle = type ? getDefaultStyle(type) : { width: 320, height: 320 }
+    const w = p.width ?? defaultStyle.width
+    const h = p.height ?? defaultStyle.height
+
+    return (
+      <div
+        style={
+          showCompact
+            ? { width: w, height: h, minWidth: w, minHeight: h, position: 'relative' }
+            : { display: 'contents' }
+        }
+      >
+        {showCompact && (
+          <CompactNodeView
+            id={p.id}
+            type={type}
+            data={p.data}
+            selected={p.selected}
+            width={p.width}
+            height={p.height}
+          />
+        )}
+        <div style={{ display: showCompact ? 'none' : undefined }} aria-hidden={showCompact}>
+          <Inner {...props} />
+        </div>
+      </div>
+    )
+  }
+
+  ContextualZoomNode.displayName = `ContextualZoom(${Inner.displayName ?? Inner.name ?? 'Node'})`
+  return ContextualZoomNode as React.ComponentType<P>
+}

frontend/src/app/canvas/ViewportDisplayContext.tsx

@@ -0,0 +1,55 @@
+/**
+ * Single subscriber for viewport zoom: one component (ViewportDisplayProvider)
+ * subscribes to useViewport() and provides displayMode so contextual nodes
+ * don't each subscribe to viewport and re-render on every pan/zoom.
+ */
+
+import React, { useLayoutEffect, useRef, useState } from 'react'
+import { useViewport } from '@xyflow/react'
+import { CONTEXTUAL_ZOOM_THRESHOLD } from '@/app/canvas/ContextualZoomNode'
+
+export type ViewportDisplayMode = 'compact' | 'full'
+
+const HYSTERESIS = 0.02
+
+const ViewportDisplayContext = React.createContext<ViewportDisplayMode>('full')
+export { ViewportDisplayContext }
+
+/**
+ * Must be rendered inside ReactFlowProvider. Subscribes to viewport once,
+ * maps zoom to displayMode with hysteresis. Throttles updates via rAF to avoid
+ * re-rendering all contextual nodes on every zoom tick.
+ */
+export function ViewportDisplayProvider({ children }: { children: React.ReactNode }) {
+  const { zoom } = useViewport()
+  const [displayMode, setDisplayMode] = useState<ViewportDisplayMode>(() =>
+    zoom <= CONTEXTUAL_ZOOM_THRESHOLD ? 'compact' : 'full'
+  )
+  const lastModeRef = useRef(displayMode)
+  const zoomRef = useRef(zoom)
+  const rafRef = useRef<number | null>(null)
+  zoomRef.current = zoom
+
+  useLayoutEffect(() => {
+    if (rafRef.current !== null) return
+    rafRef.current = requestAnimationFrame(() => {
+      rafRef.current = null
+      const z = zoomRef.current
+      const low = CONTEXTUAL_ZOOM_THRESHOLD - HYSTERESIS
+      const high = CONTEXTUAL_ZOOM_THRESHOLD + HYSTERESIS
+      let next: ViewportDisplayMode = lastModeRef.current
+      if (z <= low) next = 'compact'
+      else if (z >= high) next = 'full'
+      if (next !== lastModeRef.current) {
+        lastModeRef.current = next
+        setDisplayMode(next)
+      }
+    })
+  }, [zoom])
+
+  return (
+    <ViewportDisplayContext.Provider value={displayMode}>
+      {children}
+    </ViewportDisplayContext.Provider>
+  )
+}

frontend/src/app/canvas/canvasGraphUtils.ts

@@ -0,0 +1,84 @@
+/**
+ * Canvas graph: example graph and initial graph from storage.
+ * Used by useCanvasGraph and CanvasPage (e.g. Load example).
+ */
+
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+import { DEFAULT_NODE_STYLE } from '@/lib/graph/flowUtils'
+import { loadGraphFromStorage } from '@/app/recollections/state/recollectionGraphStorage'
+
+/** Ensure each edge has data.targetType from the target node (for labels without depending on nodes in edgesForFlow). */
+export function backfillEdgeTargetTypes(
+  nodes: AppNode[],
+  edges: AppEdge[]
+): AppEdge[] {
+  const typeById = new Map(nodes.map((n) => [n.id, n.type ?? '']))
+  return edges.map((e) => {
+    const targetType = typeById.get(e.target) ?? (e.data as Record<string, unknown>)?.targetType ?? ''
+    const data = typeof e.data === 'object' && e.data !== null ? (e.data as Record<string, unknown>) : {}
+    if (data.targetType === targetType) return e
+    return { ...e, data: { ...data, targetType } }
+  })
+}
+
+const NODE_GAP = 150
+
+const EXAMPLE_NODES: AppNode[] = [
+  {
+    id: 'var_001',
+    position: { x: 50, y: 100 },
+    data: { value: 'Zoe', valueType: 'string' as const },
+    type: 'variable',
+    style: DEFAULT_NODE_STYLE.variable,
+  },
+  {
+    id: 'cfg_001',
+    position: { x: 50 + DEFAULT_NODE_STYLE.variable.width + NODE_GAP, y: 50 },
+    data: {
+      plantuml: '@startuml\nactor User\nparticipant "{{ var_001 }}" as R\nUser -> R : loves\n@enduml\n',
+      title: 'config-cfg_001',
+    },
+    type: 'config',
+    style: DEFAULT_NODE_STYLE.config,
+  },
+  {
+    id: 'rnd_001',
+    position: {
+      x: 50 + DEFAULT_NODE_STYLE.variable.width + NODE_GAP + DEFAULT_NODE_STYLE.config.width + NODE_GAP,
+      y: 50,
+    },
+    data: {},
+    type: 'render',
+    style: DEFAULT_NODE_STYLE.render,
+  },
+]
+
+const EXAMPLE_EDGES: AppEdge[] = [
+  { id: 'e-var_001-cfg_001', source: 'var_001', target: 'cfg_001', type: 'animated' },
+  { id: 'e-cfg_001-rnd_001', source: 'cfg_001', target: 'rnd_001', type: 'animated' },
+]
+
+export function getExampleGraph(): { nodes: AppNode[]; edges: AppEdge[] } {
+  const nodes = EXAMPLE_NODES.map((n) => ({
+    ...n,
+    data: n.data && typeof n.data === 'object' ? { ...(n.data as object) } : n.data,
+  }))
+  const edges = backfillEdgeTargetTypes(
+    nodes,
+    EXAMPLE_EDGES.map((e) => ({ ...e }))
+  )
+  return { nodes, edges }
+}
+
+export function getInitialGraph(recollectionId: string | undefined): { nodes: AppNode[]; edges: AppEdge[] } {
+  if (recollectionId) {
+    const stored = loadGraphFromStorage(recollectionId)
+    if (stored && (stored.nodes.length > 0 || stored.edges.length > 0)) {
+      const nodes = stored.nodes as AppNode[]
+      const edges = backfillEdgeTargetTypes(nodes, stored.edges as AppEdge[])
+      return { nodes, edges }
+    }
+    return { nodes: [], edges: [] }
+  }
+  return getExampleGraph()
+}

frontend/src/app/canvas/canvasStore.index.ts

@@ -0,0 +1,44 @@
+/**
+ * Canvas store: centralized state + commands + selectors.
+ * Entry point for store usage.
+ */
+
+export {
+  getCanvasStore,
+  dispatchCanvasCommand,
+  useCanvasStore,
+  useCanvasStoreDispatch,
+  canvasStore,
+} from './canvasStore'
+export type { CanvasStore, CanvasCommand } from './canvasStore'
+export { initialCanvasStore, canvasStoreReducer } from './canvasStore.reducer'
+export type { CanvasStore as CanvasStoreState, PathSlice, UISlice, GraphSlice, ConnectionFrom } from './canvasStore.types'
+export {
+  selectGraph,
+  selectPath,
+  selectUI,
+  selectNodes,
+  selectEdges,
+  selectPathNodeIds,
+  selectPathActiveSegmentNodeIds,
+  selectConnectionStatusForEdge,
+  selectPathRoleForNode,
+  selectRenamingNodeId,
+  selectFullscreenNodeId,
+  selectConnectionFrom,
+  // Fine-grained selectors
+  selectNodeById,
+  selectNodesById,
+  selectNodesByType,
+  selectNodeIdsByType,
+  selectEdgesBySource,
+  selectEdgesByTarget,
+  selectEdgesForNode,
+  selectNodeCount,
+  selectEdgeCount,
+  selectHasNode,
+  selectHasEdge,
+  // SVG detection
+  isSvgContent,
+} from './canvasStore.selectors'
+export type { ConnectionPathRole } from './canvasStore.selectors'

frontend/src/app/canvas/canvasStore.reducer.ts

@@ -0,0 +1,122 @@
+/**
+ * Pure reducer for the canvas store. One command → one state transition.
+ */
+
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+import type { CanvasStore, CanvasCommand, GraphSlice, PathSlice, UISlice } from './canvasStore.types'
+
+// ---------------------------------------------------------------------------
+// Initial state
+// ---------------------------------------------------------------------------
+
+const initialGraph: GraphSlice = {
+  nodes: [],
+  edges: [],
+}
+
+const PULSE_MS = 1000
+
+const initialPath: PathSlice = {
+  triggerNodeIds: [],
+  pulseEndsAt: null,
+  errorNodeIds: [],
+}
+
+const initialUI: UISlice = {
+  renamingNodeId: null,
+  fullscreenNodeId: null,
+  connectionFrom: null,
+}
+
+export const initialCanvasStore: CanvasStore = {
+  graph: initialGraph,
+  path: initialPath,
+  ui: initialUI,
+}
+
+// ---------------------------------------------------------------------------
+// Reducer
+// ---------------------------------------------------------------------------
+
+function reduceGraph(prev: GraphSlice, cmd: CanvasCommand): GraphSlice {
+  switch (cmd.type) {
+    case 'graph/setNodes': {
+      const next =
+        typeof cmd.payload === 'function' ? cmd.payload(prev.nodes) : cmd.payload
+      return { ...prev, nodes: next }
+    }
+    case 'graph/setEdges': {
+      const next =
+        typeof cmd.payload === 'function' ? cmd.payload(prev.edges) : cmd.payload
+      return { ...prev, edges: next }
+    }
+    case 'graph/apply': {
+      return {
+        nodes: cmd.payload.nodes ?? prev.nodes,
+        edges: cmd.payload.edges ?? prev.edges,
+      }
+    }
+    default:
+      return prev
+  }
+}
+
+function reducePath(prev: PathSlice, cmd: CanvasCommand): PathSlice {
+  switch (cmd.type) {
+    case 'path/addTrigger': {
+      const id = cmd.payload
+      if (prev.triggerNodeIds.includes(id)) return prev
+      return {
+        ...prev,
+        triggerNodeIds: [...prev.triggerNodeIds, id],
+        pulseEndsAt: Date.now() + PULSE_MS,
+      }
+    }
+    case 'path/clearTriggers':
+      return { ...prev, triggerNodeIds: [], pulseEndsAt: null }
+    case 'path/setError': {
+      const { nodeId, error } = cmd.payload
+      const has = prev.errorNodeIds.includes(nodeId)
+      if (error === has) return prev
+      return {
+        ...prev,
+        errorNodeIds: error
+          ? [...prev.errorNodeIds, nodeId]
+          : prev.errorNodeIds.filter((x) => x !== nodeId),
+      }
+    }
+    case 'path/clearPathSession':
+      return { ...initialPath, errorNodeIds: prev.errorNodeIds }
+    case 'path/clearErrors':
+      return { ...prev, errorNodeIds: [] }
+    default:
+      return prev
+  }
+}
+
+function reduceUI(prev: UISlice, cmd: CanvasCommand): UISlice {
+  switch (cmd.type) {
+    case 'ui/setRenaming':
+      return { ...prev, renamingNodeId: cmd.payload }
+    case 'ui/setFullscreen':
+      return { ...prev, fullscreenNodeId: cmd.payload }
+    case 'ui/setConnectionFrom':
+      return { ...prev, connectionFrom: cmd.payload }
+    default:
+      return prev
+  }
+}
+
+export function canvasStoreReducer(state: CanvasStore, command: CanvasCommand): CanvasStore {
+  const graph = reduceGraph(state.graph, command)
+  const path = reducePath(state.path, command)
+  const ui = reduceUI(state.ui, command)
+  if (
+    graph === state.graph &&
+    path === state.path &&
+    ui === state.ui
+  ) {
+    return state
+  }
+  return { graph, path, ui }
+}

frontend/src/app/canvas/canvasStore.selectors.ts

@@ -0,0 +1,205 @@
+/**
+ * Selectors for the canvas store. Pure (state) => value.
+ * Derived path sets (pathNodeIds, pausedSegmentNodeIds, activeSegmentNodeIds) are computed here.
+ */
+
+import {
+  getPathNodeIds,
+  getPathToUpdatingSegmentNodeIds,
+  type NodeAttributesMap,
+} from '@/lib/graph/graphologyPath'
+import { getConnectionStatus, type ConnectionStatus } from '@/lib/graph/connectionStatus'
+import type { CanvasStore } from './canvasStore.types'
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+
+export type ConnectionPathRole = 'trigger' | 'on-path' | null
+
+// ---------------------------------------------------------------------------
+// SVG Detection - Centralized logic for detecting SVG content
+// ---------------------------------------------------------------------------
+
+/** Check if a string contains SVG content. */
+export function isSvgContent(content: string | null | undefined): boolean {
+  return Boolean(content?.trim() && /<svg[\s>]/i.test(content.trim()))
+}
+
+// ---------------------------------------------------------------------------
+// Raw slices
+// ---------------------------------------------------------------------------
+
+export function selectGraph(state: CanvasStore) {
+  return state.graph
+}
+
+export function selectPath(state: CanvasStore) {
+  return state.path
+}
+
+export function selectUI(state: CanvasStore) {
+  return state.ui
+}
+
+export function selectNodes(state: CanvasStore) {
+  return state.graph.nodes
+}
+
+export function selectEdges(state: CanvasStore) {
+  return state.graph.edges
+}
+
+// ---------------------------------------------------------------------------
+// Fine-grained selectors for optimal re-rendering
+// ---------------------------------------------------------------------------
+
+/** Get a specific node by ID. */
+export function selectNodeById(state: CanvasStore, nodeId: string): AppNode | undefined {
+  return state.graph.nodes.find((n) => n.id === nodeId)
+}
+
+/** Get multiple nodes by IDs. */
+export function selectNodesById(state: CanvasStore, nodeIds: string[]): AppNode[] {
+  return state.graph.nodes.filter((n) => nodeIds.includes(n.id))
+}
+
+/** Get nodes by type. */
+export function selectNodesByType(state: CanvasStore, nodeType: string): AppNode[] {
+  return state.graph.nodes.filter((n) => n.type === nodeType)
+}
+
+/** Get node IDs by type. */
+export function selectNodeIdsByType(state: CanvasStore, nodeType: string): string[] {
+  return state.graph.nodes.filter((n) => n.type === nodeType).map((n) => n.id)
+}
+
+/** Get edges by source node ID. */
+export function selectEdgesBySource(state: CanvasStore, sourceId: string): AppEdge[] {
+  return state.graph.edges.filter((e) => e.source === sourceId)
+}
+
+/** Get edges by target node ID. */
+export function selectEdgesByTarget(state: CanvasStore, targetId: string): AppEdge[] {
+  return state.graph.edges.filter((e) => e.target === targetId)
+}
+
+/** Get all edges connected to a node (source or target). */
+export function selectEdgesForNode(state: CanvasStore, nodeId: string): AppEdge[] {
+  return state.graph.edges.filter((e) => e.source === nodeId || e.target === nodeId)
+}
+
+/** Get node count. */
+export function selectNodeCount(state: CanvasStore): number {
+  return state.graph.nodes.length
+}
+
+/** Get edge count. */
+export function selectEdgeCount(state: CanvasStore): number {
+  return state.graph.edges.length
+}
+
+/** Check if a node exists. */
+export function selectHasNode(state: CanvasStore, nodeId: string): boolean {
+  return state.graph.nodes.some((n) => n.id === nodeId)
+}
+
+/** Check if an edge exists. */
+export function selectHasEdge(state: CanvasStore, source: string, target: string): boolean {
+  return state.graph.edges.some((e) => e.source === source && e.target === target)
+}
+
+// ---------------------------------------------------------------------------
+// Derived path (Sets) – depend on graph.edges + path primitive arrays
+// ---------------------------------------------------------------------------
+
+const emptySet = new Set<string>()
+
+function edgesAsGraphEdges(edges: CanvasStore['graph']['edges']) {
+  return edges.map((e) => ({ source: e.source, target: e.target, id: e.id }))
+}
+
+/** Build node attributes for graphology (nodeType, updateMode) from canvas nodes. */
+function buildNodeAttributesMap(nodes: AppNode[]): NodeAttributesMap {
+  const map: NodeAttributesMap = {}
+  for (const n of nodes) {
+    const data = n.data as { updateMode?: 'auto' | 'manual' } | undefined
+    map[n.id] = {
+      nodeType: n.type ?? undefined,
+      updateMode: data?.updateMode,
+    }
+  }
+  return map
+}
+
+export function selectPathNodeIds(state: CanvasStore): Set<string> {
+  const { nodes, edges } = state.graph
+  const { triggerNodeIds } = state.path
+  return getPathNodeIds(
+    edgesAsGraphEdges(edges),
+    [],
+    triggerNodeIds,
+    undefined,
+    buildNodeAttributesMap(nodes)
+  )
+}
+
+export function selectPathActiveSegmentNodeIds(state: CanvasStore): Set<string> {
+  const { nodes, edges } = state.graph
+  const { triggerNodeIds, pulseEndsAt } = state.path
+  const pulseActive = pulseEndsAt != null
+  return getPathToUpdatingSegmentNodeIds(
+    edgesAsGraphEdges(edges),
+    triggerNodeIds,
+    pulseActive,
+    buildNodeAttributesMap(nodes)
+  )
+}
+
+// ---------------------------------------------------------------------------
+// Per-edge connection status (for AnimatedEdge)
+// ---------------------------------------------------------------------------
+
+export function selectConnectionStatusForEdge(
+  state: CanvasStore,
+  source: string,
+  target: string
+): ConnectionStatus {
+  const pathNodeIds = selectPathNodeIds(state)
+  const activeSegmentNodeIds = selectPathActiveSegmentNodeIds(state)
+  const errorTargetNodeIds = new Set(state.path.errorNodeIds)
+  return getConnectionStatus({
+    source,
+    target,
+    pathNodeIds,
+    activeSegmentNodeIds,
+    errorTargetNodeIds,
+  })
+}
+
+// ---------------------------------------------------------------------------
+// Per-node path role (for BaseNode styling)
+// ---------------------------------------------------------------------------
+
+export function selectPathRoleForNode(
+  state: CanvasStore,
+  nodeId: string
+): ConnectionPathRole {
+  const pathNodeIds = selectPathNodeIds(state)
+  if (!pathNodeIds.has(nodeId)) return null
+  if (state.path.triggerNodeIds.includes(nodeId)) return 'trigger'
+  return 'on-path'
+}
+
+// ---------------------------------------------------------------------------
+// UI
+// ---------------------------------------------------------------------------
+
+export function selectRenamingNodeId(state: CanvasStore): string | null {
+  return state.ui.renamingNodeId
+}
+
+export function selectFullscreenNodeId(state: CanvasStore): string | null {
+  return state.ui.fullscreenNodeId
+}
+
+export function selectConnectionFrom(state: CanvasStore) {
+  return state.ui.connectionFrom
+}

frontend/src/app/canvas/canvasStore.test.ts

@@ -0,0 +1,504 @@
+import { describe, it, expect, beforeEach } from 'vitest'
+import {
+  initialCanvasStore,
+  canvasStoreReducer,
+  getCanvasStore,
+  dispatchCanvasCommand,
+} from './canvasStore'
+import {
+  selectPathNodeIds,
+  selectPathActiveSegmentNodeIds,
+  selectConnectionStatusForEdge,
+  selectPathRoleForNode,
+  selectNodes,
+  selectEdges,
+  selectRenamingNodeId,
+  selectFullscreenNodeId,
+  selectConnectionFrom,
+} from './canvasStore.selectors'
+import type { CanvasStore, CanvasCommand } from './canvasStore.types'
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+
+// ---------------------------------------------------------------------------
+// Fixtures
+// ---------------------------------------------------------------------------
+
+function makeNode(id: string, type = 'config'): AppNode {
+  return {
+    id,
+    type,
+    position: { x: 0, y: 0 },
+    data: {},
+  }
+}
+
+function makeEdge(id: string, source: string, target: string): AppEdge {
+  return { id, source, target }
+}
+
+// ---------------------------------------------------------------------------
+// Reducer: graph commands
+// ---------------------------------------------------------------------------
+
+describe('canvasStoreReducer', () => {
+  describe('graph commands', () => {
+    it('graph/setNodes replaces nodes', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        graph: {
+          nodes: [makeNode('a')],
+          edges: [],
+        },
+      }
+      const next = canvasStoreReducer(state, {
+        type: 'graph/setNodes',
+        payload: [makeNode('b'), makeNode('c')],
+      })
+      expect(next.graph.nodes).toHaveLength(2)
+      expect(next.graph.nodes.map((n) => n.id)).toEqual(['b', 'c'])
+      expect(next.graph.edges).toEqual(state.graph.edges)
+    })
+
+    it('graph/setNodes with updater function', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        graph: {
+          nodes: [makeNode('a'), makeNode('b')],
+          edges: [],
+        },
+      }
+      const next = canvasStoreReducer(state, {
+        type: 'graph/setNodes',
+        payload: (prev) => prev.filter((n) => n.id !== 'a'),
+      })
+      expect(next.graph.nodes).toHaveLength(1)
+      expect(next.graph.nodes[0].id).toBe('b')
+    })
+
+    it('graph/setEdges replaces edges', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        graph: {
+          nodes: [],
+          edges: [makeEdge('e1', 'a', 'b')],
+        },
+      }
+      const next = canvasStoreReducer(state, {
+        type: 'graph/setEdges',
+        payload: [makeEdge('e2', 'b', 'c')],
+      })
+      expect(next.graph.edges).toHaveLength(1)
+      expect(next.graph.edges[0].id).toBe('e2')
+    })
+
+    it('graph/apply updates nodes and edges', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        graph: {
+          nodes: [makeNode('a')],
+          edges: [makeEdge('e1', 'a', 'b')],
+        },
+      }
+      const next = canvasStoreReducer(state, {
+        type: 'graph/apply',
+        payload: { nodes: [makeNode('x')] },
+      })
+      expect(next.graph.nodes).toHaveLength(1)
+      expect(next.graph.nodes[0].id).toBe('x')
+      expect(next.graph.edges).toEqual(state.graph.edges)
+    })
+  })
+
+  describe('path commands', () => {
+    it('path/addTrigger adds node id', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      const next = canvasStoreReducer(state, {
+        type: 'path/addTrigger',
+        payload: 'n1',
+      })
+      expect(next.path.triggerNodeIds).toEqual(['n1'])
+    })
+
+    it('path/addTrigger is idempotent', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        path: { ...initialCanvasStore.path, triggerNodeIds: ['n1'] },
+      }
+      const next = canvasStoreReducer(state, {
+        type: 'path/addTrigger',
+        payload: 'n1',
+      })
+      expect(next).toBe(state)
+    })
+
+    it('path/clearTriggers empties triggerNodeIds and pulseEndsAt', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        path: {
+          triggerNodeIds: ['a', 'b'],
+          pulseEndsAt: Date.now() + 1000,
+          errorNodeIds: [],
+        },
+      }
+      const next = canvasStoreReducer(state, { type: 'path/clearTriggers' })
+      expect(next.path.triggerNodeIds).toEqual([])
+      expect(next.path.pulseEndsAt).toBeNull()
+    })
+
+    it('path/addTrigger sets pulseEndsAt', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      const before = Date.now()
+      const next = canvasStoreReducer(state, {
+        type: 'path/addTrigger',
+        payload: 'n1',
+      })
+      expect(next.path.triggerNodeIds).toEqual(['n1'])
+      expect(next.path.pulseEndsAt).toBeGreaterThanOrEqual(before + 1000)
+    })
+
+    it('path/setError adds and removes error node', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      let next = canvasStoreReducer(state, {
+        type: 'path/setError',
+        payload: { nodeId: 'n1', error: true },
+      })
+      expect(next.path.errorNodeIds).toEqual(['n1'])
+      next = canvasStoreReducer(next, {
+        type: 'path/setError',
+        payload: { nodeId: 'n1', error: false },
+      })
+      expect(next.path.errorNodeIds).toEqual([])
+    })
+
+    it('path/clearPathSession resets trigger and pulse; keeps error', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        path: {
+          triggerNodeIds: ['t1'],
+          pulseEndsAt: Date.now() + 1000,
+          errorNodeIds: ['e1'],
+        },
+      }
+      const next = canvasStoreReducer(state, { type: 'path/clearPathSession' })
+      expect(next.path.triggerNodeIds).toEqual([])
+      expect(next.path.pulseEndsAt).toBeNull()
+      expect(next.path.errorNodeIds).toEqual(['e1'])
+    })
+  })
+
+  describe('ui commands', () => {
+    it('ui/setRenaming updates renamingNodeId', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      const next = canvasStoreReducer(state, {
+        type: 'ui/setRenaming',
+        payload: 'node-1',
+      })
+      expect(next.ui.renamingNodeId).toBe('node-1')
+    })
+
+    it('ui/setFullscreen updates fullscreenNodeId', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      const next = canvasStoreReducer(state, {
+        type: 'ui/setFullscreen',
+        payload: 'node-2',
+      })
+      expect(next.ui.fullscreenNodeId).toBe('node-2')
+    })
+
+    it('ui/setConnectionFrom updates connectionFrom', () => {
+      const state: CanvasStore = { ...initialCanvasStore }
+      const next = canvasStoreReducer(state, {
+        type: 'ui/setConnectionFrom',
+        payload: { nodeId: 'n1', sourceHandle: 'out' },
+      })
+      expect(next.ui.connectionFrom).toEqual({ nodeId: 'n1', sourceHandle: 'out' })
+    })
+  })
+
+  describe('no-op returns same reference', () => {
+    it('path/addTrigger with existing id returns state', () => {
+      const state: CanvasStore = {
+        ...initialCanvasStore,
+        path: { ...initialCanvasStore.path, triggerNodeIds: ['a'] },
+      }
+      const next = canvasStoreReducer(state, { type: 'path/addTrigger', payload: 'a' })
+      expect(next).toBe(state)
+    })
+  })
+
+  describe('initial path shape', () => {
+    it('path has triggerNodeIds, pulseEndsAt, errorNodeIds; no updatingNodeIds', () => {
+      const path = initialCanvasStore.path
+      expect(path).toHaveProperty('triggerNodeIds')
+      expect(path).toHaveProperty('pulseEndsAt')
+      expect(path).toHaveProperty('errorNodeIds')
+      expect(path.triggerNodeIds).toEqual([])
+      expect(path.pulseEndsAt).toBeNull()
+      expect(path.errorNodeIds).toEqual([])
+      expect(path).not.toHaveProperty('updatingNodeIds')
+    })
+  })
+})
+
+// ---------------------------------------------------------------------------
+// Selectors
+// ---------------------------------------------------------------------------
+
+describe('canvasStore selectors', () => {
+  it('selectNodes and selectEdges return graph slice', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [makeNode('a')],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+    }
+    expect(selectNodes(state)).toHaveLength(1)
+    expect(selectEdges(state)).toHaveLength(1)
+  })
+
+  it('selectPathNodeIds derives path from edges and path arrays', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [makeNode('a'), makeNode('b'), makeNode('c')],
+        edges: [
+          makeEdge('e1', 'a', 'b'),
+          makeEdge('e2', 'b', 'c'),
+        ],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: null,
+        errorNodeIds: [],
+      },
+    }
+    const pathIds = selectPathNodeIds(state)
+    expect(pathIds.has('a')).toBe(true)
+    expect(pathIds.has('b')).toBe(true)
+    expect(pathIds.has('c')).toBe(true)
+  })
+
+  it('selectConnectionStatusForEdge returns default when edge not on path', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: { nodes: [], edges: [makeEdge('e1', 'a', 'b')] },
+      path: initialCanvasStore.path,
+    }
+    expect(selectConnectionStatusForEdge(state, 'a', 'b')).toBe('default')
+  })
+
+  it('selectConnectionStatusForEdge returns default when on path but pulse inactive', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: null,
+        errorNodeIds: [],
+      },
+    }
+    expect(selectPathNodeIds(state).has('a')).toBe(true)
+    expect(selectPathNodeIds(state).has('b')).toBe(true)
+    expect(selectConnectionStatusForEdge(state, 'a', 'b')).toBe('default')
+  })
+
+  it('selectConnectionStatusForEdge returns updating when on path and pulse active', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: Date.now() + 2000,
+        errorNodeIds: [],
+      },
+    }
+    expect(selectConnectionStatusForEdge(state, 'a', 'b')).toBe('updating')
+  })
+
+  it('selectConnectionStatusForEdge returns error over updating when target has error', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: Date.now() + 2000,
+        errorNodeIds: ['b'],
+      },
+    }
+    expect(selectConnectionStatusForEdge(state, 'a', 'b')).toBe('error')
+  })
+
+  it('selectPathActiveSegmentNodeIds is empty when pulse inactive', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: null,
+        errorNodeIds: [],
+      },
+    }
+    const active = selectPathActiveSegmentNodeIds(state)
+    expect(active.size).toBe(0)
+  })
+
+  it('selectPathActiveSegmentNodeIds returns downstream of trigger when pulse active', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [
+          makeEdge('e1', 'a', 'b'),
+          makeEdge('e2', 'b', 'c'),
+        ],
+      },
+      path: {
+        triggerNodeIds: ['a'],
+        pulseEndsAt: Date.now() + 2000,
+        errorNodeIds: [],
+      },
+    }
+    const active = selectPathActiveSegmentNodeIds(state)
+    expect(active.has('a')).toBe(true)
+    expect(active.has('b')).toBe(true)
+    expect(active.has('c')).toBe(true)
+  })
+
+  it('selectPathRoleForNode returns trigger or on-path', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      graph: {
+        nodes: [],
+        edges: [makeEdge('e1', 'a', 'b')],
+      },
+      path: {
+        ...initialCanvasStore.path,
+        triggerNodeIds: ['a'],
+        pulseEndsAt: null,
+        errorNodeIds: [],
+      },
+    }
+    expect(selectPathRoleForNode(state, 'a')).toBe('trigger')
+    expect(selectPathRoleForNode(state, 'b')).toBe('on-path')
+    expect(selectPathRoleForNode(state, 'x')).toBe(null)
+  })
+
+  it('selectRenamingNodeId, selectFullscreenNodeId, selectConnectionFrom return ui slice', () => {
+    const state: CanvasStore = {
+      ...initialCanvasStore,
+      ui: {
+        renamingNodeId: 'r1',
+        fullscreenNodeId: 'f1',
+        connectionFrom: { nodeId: 'c1' },
+      },
+    }
+    expect(selectRenamingNodeId(state)).toBe('r1')
+    expect(selectFullscreenNodeId(state)).toBe('f1')
+    expect(selectConnectionFrom(state)).toEqual({ nodeId: 'c1' })
+  })
+})
+
+// ---------------------------------------------------------------------------
+// Store integration (dispatch + getState)
+// ---------------------------------------------------------------------------
+
+describe('canvas store integration', () => {
+  beforeEach(() => {
+    dispatchCanvasCommand({ type: 'graph/setNodes', payload: [] })
+    dispatchCanvasCommand({ type: 'graph/setEdges', payload: [] })
+    dispatchCanvasCommand({ type: 'path/clearPathSession' })
+    dispatchCanvasCommand({ type: 'path/clearTriggers' })
+    dispatchCanvasCommand({ type: 'path/clearErrors' })
+    dispatchCanvasCommand({ type: 'ui/setRenaming', payload: null })
+    dispatchCanvasCommand({ type: 'ui/setFullscreen', payload: null })
+    dispatchCanvasCommand({ type: 'ui/setConnectionFrom', payload: null })
+  })
+
+  it('dispatch graph/setNodes updates getCanvasStore().graph.nodes', () => {
+    const node = makeNode('test-1')
+    dispatchCanvasCommand({ type: 'graph/setNodes', payload: [node] })
+    const state = getCanvasStore()
+    expect(state.graph.nodes).toHaveLength(1)
+    expect(state.graph.nodes[0].id).toBe('test-1')
+  })
+
+  it('dispatch path/addTrigger updates path and starts pulse', () => {
+    dispatchCanvasCommand({ type: 'graph/setNodes', payload: [makeNode('a'), makeNode('b')] })
+    dispatchCanvasCommand({ type: 'graph/setEdges', payload: [makeEdge('e1', 'a', 'b')] })
+    dispatchCanvasCommand({ type: 'path/addTrigger', payload: 'a' })
+    const state = getCanvasStore()
+    expect(state.path.triggerNodeIds).toContain('a')
+    expect(state.path.pulseEndsAt).not.toBeNull()
+    const pathIds = selectPathNodeIds(state)
+    expect(pathIds.has('a')).toBe(true)
+    expect(pathIds.has('b')).toBe(true)
+  })
+
+  it('dispatch ui/setFullscreen updates getCanvasStore().ui', () => {
+    dispatchCanvasCommand({ type: 'ui/setFullscreen', payload: 'full-node' })
+    const state = getCanvasStore()
+    expect(state.ui.fullscreenNodeId).toBe('full-node')
+  })
+
+  // Pulse: addTrigger starts a short "updating" pulse along downstream path.
+  it('path-per-sink: addTrigger starts pulse, all downstream edges show updating', () => {
+    const nodes: AppNode[] = [
+      {
+        id: 'var_001',
+        type: 'variable',
+        position: { x: -270, y: 210 },
+        data: { value: 'sss', valueType: 'string' },
+      },
+      {
+        id: 'cfg_001',
+        type: 'config',
+        position: { x: 180, y: 330 },
+        data: { configType: 'plantuml', content: '@startuml\nactor Mulis\n@enduml\n', title: 'cfg_001' },
+      },
+      {
+        id: 'rnd_001',
+        type: 'render',
+        position: { x: 780, y: 540 },
+        data: { updateMode: 'manual', runTrigger: 1, lastRunSourceSignature: 'sig1' },
+      },
+      {
+        id: 'rnd_002',
+        type: 'render',
+        position: { x: 780, y: 180 },
+        data: { updateMode: 'auto', runTrigger: 2, lastRunSourceSignature: 'sig2' },
+      },
+    ]
+    const edges: AppEdge[] = [
+      { id: 'xy-edge__var_001out-cfg_001ain', source: 'var_001', target: 'cfg_001', data: { targetType: 'config' } },
+      { id: 'xy-edge__cfg_001out-rnd_001ain', source: 'cfg_001', target: 'rnd_001', data: { targetType: 'render' } },
+      { id: 'xy-edge__cfg_001out-rnd_002ain', source: 'cfg_001', target: 'rnd_002', data: { targetType: 'render' } },
+    ]
+    dispatchCanvasCommand({ type: 'graph/apply', payload: { nodes, edges } })
+    dispatchCanvasCommand({ type: 'path/addTrigger', payload: 'var_001' })
+
+    const state = getCanvasStore()
+    const pathIds = selectPathNodeIds(state)
+    expect(pathIds.has('var_001')).toBe(true)
+    expect(pathIds.has('cfg_001')).toBe(true)
+    expect(pathIds.has('rnd_001')).toBe(true)
+    expect(pathIds.has('rnd_002')).toBe(true)
+
+    // During pulse, all path edges show "updating".
+    expect(selectConnectionStatusForEdge(state, 'var_001', 'cfg_001')).toBe('updating')
+    expect(selectConnectionStatusForEdge(state, 'cfg_001', 'rnd_001')).toBe('updating')
+    expect(selectConnectionStatusForEdge(state, 'cfg_001', 'rnd_002')).toBe('updating')
+  })
+})

frontend/src/app/canvas/canvasStore.ts

@@ -0,0 +1,74 @@
+/**
+ * Centralized canvas store (Zustand). Single source of truth for graph, path, and UI.
+ * Mutate only via dispatch(command); read via useCanvasStore(selector) or getCanvasStore().
+ */
+
+import { createStore, useStore } from 'zustand'
+import type { CanvasStore as CanvasStoreState, CanvasCommand } from './canvasStore.types'
+import { initialCanvasStore, canvasStoreReducer } from './canvasStore.reducer'
+
+// ---------------------------------------------------------------------------
+// Store type (state + dispatch)
+// ---------------------------------------------------------------------------
+
+export type CanvasStoreWithDispatch = CanvasStoreState & {
+  dispatch: (command: CanvasCommand) => void
+}
+
+// ---------------------------------------------------------------------------
+// Create store
+// ---------------------------------------------------------------------------
+
+function createCanvasStore() {
+  return createStore<CanvasStoreWithDispatch>((set, get) => {
+    const applyCommand = (command: CanvasCommand) => {
+      const prev = get()
+      const next = canvasStoreReducer(prev, command)
+      if (next === prev) return
+      set({ ...next, dispatch: prev.dispatch })
+    }
+    const dispatch: (command: CanvasCommand) => void =
+      typeof import.meta !== 'undefined' && import.meta.env?.DEV
+        ? (command) => {
+            // eslint-disable-next-line no-console
+            console.log('[canvas]', command.type, command.payload)
+            applyCommand(command)
+          }
+        : applyCommand
+    return { ...initialCanvasStore, dispatch }
+  })
+}
+
+const canvasStore = createCanvasStore()
+
+// ---------------------------------------------------------------------------
+// Public API
+// ---------------------------------------------------------------------------
+
+/** Get current state (for use outside React or in selectors). Excludes dispatch. */
+export function getCanvasStore(): CanvasStoreState {
+  const s = canvasStore.getState()
+  return { graph: s.graph, path: s.path, ui: s.ui }
+}
+
+/** Dispatch a command. Use for all mutations. */
+export function dispatchCanvasCommand(command: CanvasCommand): void {
+  canvasStore.getState().dispatch(command)
+}
+
+/**
+ * Subscribe to the store. Pass a selector to re-render only when the selected value changes.
+ * For object/array selectors consider useShallow from 'zustand/react/shallow' to avoid unnecessary re-renders.
+ */
+export function useCanvasStore<T>(selector: (state: CanvasStoreState) => T): T {
+  return useStore(canvasStore, selector)
+}
+
+/** Hook that returns dispatch (stable reference). */
+export function useCanvasStoreDispatch(): (command: CanvasCommand) => void {
+  return useStore(canvasStore, (s) => s.dispatch, Object.is)
+}
+
+export { canvasStore, initialCanvasStore, canvasStoreReducer }
+export type { CanvasStoreState as CanvasStore }
+export type { CanvasCommand }

frontend/src/app/canvas/canvasStore.types.ts

@@ -0,0 +1,66 @@
+/**
+ * Canvas store: types for the centralized store (graph + path + ui).
+ * All mutations go through commands; reads go through selectors.
+ */
+
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+
+// ---------------------------------------------------------------------------
+// Graph slice
+// ---------------------------------------------------------------------------
+
+export type GraphSlice = {
+  nodes: AppNode[]
+  edges: AppEdge[]
+}
+
+// ---------------------------------------------------------------------------
+// Path slice (primitive arrays; derived Sets are in selectors)
+// ---------------------------------------------------------------------------
+
+/** Pulse: "updating" shows along path for a short time after a trigger; no node start/end. */
+export type PathSlice = {
+  triggerNodeIds: string[]
+  /** When non-null, path from triggers shows "updating" until this time (ms). Cleared by timer. */
+  pulseEndsAt: number | null
+  errorNodeIds: string[]
+}
+
+// ---------------------------------------------------------------------------
+// UI slice
+// ---------------------------------------------------------------------------
+
+export type ConnectionFrom = { nodeId: string; sourceHandle?: string } | null
+
+export type UISlice = {
+  renamingNodeId: string | null
+  fullscreenNodeId: string | null
+  connectionFrom: ConnectionFrom
+}
+
+// ---------------------------------------------------------------------------
+// Full store
+// ---------------------------------------------------------------------------
+
+export type CanvasStore = {
+  graph: GraphSlice
+  path: PathSlice
+  ui: UISlice
+}
+
+// ---------------------------------------------------------------------------
+// Commands (discriminated union)
+// ---------------------------------------------------------------------------
+
+export type CanvasCommand =
+  | { type: 'graph/setNodes'; payload: AppNode[] | ((prev: AppNode[]) => AppNode[]) }
+  | { type: 'graph/setEdges'; payload: AppEdge[] | ((prev: AppEdge[]) => AppEdge[]) }
+  | { type: 'graph/apply'; payload: { nodes?: AppNode[]; edges?: AppEdge[] } }
+  | { type: 'path/addTrigger'; payload: string }
+  | { type: 'path/clearTriggers' }
+  | { type: 'path/setError'; payload: { nodeId: string; error: boolean } }
+  | { type: 'path/clearPathSession' }
+  | { type: 'path/clearErrors' }
+  | { type: 'ui/setRenaming'; payload: string | null }
+  | { type: 'ui/setFullscreen'; payload: string | null }
+  | { type: 'ui/setConnectionFrom'; payload: ConnectionFrom }

frontend/src/app/canvas/useCanvasConnectionPath.ts

@@ -0,0 +1,155 @@
+/**
+ * Hook that holds all connection-path state and callbacks for the canvas.
+ * Used to show the "ant trail" along the path of an update (e.g. config → agent → render).
+ * Extracted from CanvasPage to keep the page focused on composition.
+ */
+
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
+import { getPathNodeIds, getPathToUpdatingSegmentNodeIds } from '@/lib/graph/graphPath'
+
+/** Serialize set to a stable string for equality. */
+function setToStableKey(s: Set<string>): string {
+  return Array.from(s).sort().join(',')
+}
+
+export type EdgeLike = { source: string; target: string }
+
+const PULSE_MS = 1500
+
+export type UseCanvasConnectionPathResult = {
+  connectionPathUpdatingNodeIds: string[]
+  connectionPathTriggerNodeIds: string[]
+  connectionPathPausedNodeIds: string[]
+  connectionPathErrorNodeIds: string[]
+  connectionPathNodeIds: Set<string>
+  connectionPathPausedSegmentNodeIds: Set<string>
+  connectionPathActiveSegmentNodeIds: Set<string>
+  startConnectionPathUpdate: (nodeId: string) => void
+  endConnectionPathUpdate: (nodeId: string) => void
+  addConnectionPathTrigger: (nodeId: string) => void
+  addConnectionPathPausedNode: (nodeId: string) => void
+  removeConnectionPathPausedNode: (nodeId: string) => void
+  addConnectionPathError: (nodeId: string) => void
+  removeConnectionPathError: (nodeId: string) => void
+}
+
+export function useCanvasConnectionPath(edges: EdgeLike[]): UseCanvasConnectionPathResult {
+  const [connectionPathTriggerNodeIds, setConnectionPathTriggerNodeIds] = useState<string[]>([])
+  const [pulseEndsAt, setPulseEndsAt] = useState<number | null>(null)
+  const [connectionPathErrorNodeIds, setConnectionPathErrorNodeIds] = useState<string[]>([])
+
+  const pathTriggerBatchRef = useRef<Set<string>>(new Set())
+  const pathTriggerScheduledRef = useRef(false)
+  const pulseTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+
+  const addConnectionPathTrigger = useCallback((nodeId: string) => {
+    pathTriggerBatchRef.current.add(nodeId)
+    if (pathTriggerScheduledRef.current) return
+    pathTriggerScheduledRef.current = true
+    requestAnimationFrame(() => {
+      pathTriggerScheduledRef.current = false
+      const batch = new Set(pathTriggerBatchRef.current)
+      pathTriggerBatchRef.current = new Set()
+      if (batch.size === 0) return
+      setConnectionPathTriggerNodeIds((prev) => {
+        const next = new Set(prev)
+        batch.forEach((id) => next.add(id))
+        return next.size === prev.length && prev.every((id) => next.has(id)) ? prev : Array.from(next)
+      })
+      setPulseEndsAt(Date.now() + PULSE_MS)
+    })
+  }, [])
+
+  useEffect(() => {
+    if (pulseEndsAt == null) return
+    const delay = Math.max(0, pulseEndsAt - Date.now())
+    if (pulseTimerRef.current != null) clearTimeout(pulseTimerRef.current)
+    pulseTimerRef.current = setTimeout(() => {
+      pulseTimerRef.current = null
+      setPulseEndsAt(null)
+      setConnectionPathTriggerNodeIds([])
+    }, delay)
+    return () => {
+      if (pulseTimerRef.current != null) {
+        clearTimeout(pulseTimerRef.current)
+        pulseTimerRef.current = null
+      }
+    }
+  }, [pulseEndsAt])
+
+  const connectionPathNodeIdsRaw = useMemo(
+    () =>
+      getPathNodeIds(edges, [], connectionPathTriggerNodeIds, undefined),
+    [edges, connectionPathTriggerNodeIds]
+  )
+  const connectionPathNodeIdsRef = useRef<Set<string>>(connectionPathNodeIdsRaw)
+  const connectionPathNodeIdsKeyRef = useRef<string>('')
+  const connectionPathNodeIds =
+    setToStableKey(connectionPathNodeIdsRaw) === connectionPathNodeIdsKeyRef.current
+      ? connectionPathNodeIdsRef.current
+      : (() => {
+          connectionPathNodeIdsKeyRef.current = setToStableKey(connectionPathNodeIdsRaw)
+          connectionPathNodeIdsRef.current = connectionPathNodeIdsRaw
+          return connectionPathNodeIdsRaw
+        })()
+
+  const EMPTY_PAUSED_SEGMENT = useMemo(() => new Set<string>(), [])
+  const connectionPathPausedSegmentNodeIds = EMPTY_PAUSED_SEGMENT
+
+  const pulseActive = pulseEndsAt != null
+  const connectionPathActiveSegmentNodeIdsRaw = useMemo(
+    () =>
+      getPathToUpdatingSegmentNodeIds(
+        edges,
+        connectionPathTriggerNodeIds,
+        pulseActive
+      ),
+    [edges, connectionPathTriggerNodeIds, pulseActive]
+  )
+  const connectionPathActiveSegmentNodeIdsRef = useRef<Set<string>>(
+    connectionPathActiveSegmentNodeIdsRaw
+  )
+  const connectionPathActiveSegmentNodeIdsKeyRef = useRef<string>('')
+  const connectionPathActiveSegmentNodeIds =
+    setToStableKey(connectionPathActiveSegmentNodeIdsRaw) ===
+    connectionPathActiveSegmentNodeIdsKeyRef.current
+      ? connectionPathActiveSegmentNodeIdsRef.current
+      : (() => {
+          connectionPathActiveSegmentNodeIdsKeyRef.current = setToStableKey(
+            connectionPathActiveSegmentNodeIdsRaw
+          )
+          connectionPathActiveSegmentNodeIdsRef.current = connectionPathActiveSegmentNodeIdsRaw
+          return connectionPathActiveSegmentNodeIdsRaw
+        })()
+
+  const addConnectionPathPausedNode = useCallback((_nodeId: string) => {}, [])
+  const removeConnectionPathPausedNode = useCallback((_nodeId: string) => {}, [])
+
+  const startConnectionPathUpdate = useCallback((_nodeId: string) => {}, [])
+  const endConnectionPathUpdate = useCallback((_nodeId: string) => {}, [])
+
+  const addConnectionPathError = useCallback((nodeId: string) => {
+    setConnectionPathErrorNodeIds((prev) => (prev.includes(nodeId) ? prev : [...prev, nodeId]))
+  }, [])
+
+  const removeConnectionPathError = useCallback((nodeId: string) => {
+    setConnectionPathErrorNodeIds((prev) => prev.filter((id) => id !== nodeId))
+  }, [])
+
+  return {
+    connectionPathUpdatingNodeIds: [],
+    connectionPathTriggerNodeIds,
+    connectionPathPausedNodeIds: [],
+    connectionPathErrorNodeIds,
+    connectionPathNodeIds,
+    connectionPathPausedSegmentNodeIds,
+    connectionPathActiveSegmentNodeIds,
+    startConnectionPathUpdate,
+    endConnectionPathUpdate,
+    addConnectionPathTrigger,
+    addConnectionPathPausedNode,
+    removeConnectionPathPausedNode,
+    addConnectionPathError,
+    removeConnectionPathError,
+  }
+}

frontend/src/app/canvas/useCanvasConnectionPathFromStore.ts

@@ -0,0 +1,128 @@
+/**
+ * Connection-path state and callbacks backed by the canvas store.
+ * "Updating" is time-bound: when a trigger is added, the path pulses for a short time
+ * and then clears. No node start/end reporting.
+ */
+
+import { useCallback, useEffect, useMemo, useRef } from 'react'
+import {
+  dispatchCanvasCommand,
+  useCanvasStore,
+} from '@/app/canvas/canvasStore'
+import {
+  selectPathRoleForNode,
+  type ConnectionPathRole,
+} from '@/app/canvas/canvasStore.selectors'
+import { getPathNodeIds, getPathToUpdatingSegmentNodeIds } from '@/lib/graph/graphologyPath'
+import type { UseCanvasConnectionPathResult } from './useCanvasConnectionPath'
+
+const EMPTY_PAUSED_SEGMENT = new Set<string>()
+
+function edgesAsGraphEdges(
+  edges: Array<{ source: string; target: string }>
+): Array<{ source: string; target: string }> {
+  return edges.map((e) => ({ source: e.source, target: e.target }))
+}
+
+export function useCanvasConnectionPathFromStore(): UseCanvasConnectionPathResult {
+  const path = useCanvasStore((s) => s.path)
+  const edges = useCanvasStore((s) => s.graph.edges)
+  const pulseEndsAtRef = useRef<number | null>(null)
+  const pulseTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+
+  const pathNodeIds = useMemo(
+    () =>
+      getPathNodeIds(
+        edgesAsGraphEdges(edges),
+        [],
+        path.triggerNodeIds,
+        undefined
+      ),
+    [edges, path.triggerNodeIds]
+  )
+  const pulseActive = path.pulseEndsAt != null
+  const connectionPathActiveSegmentNodeIds = useMemo(
+    () =>
+      getPathToUpdatingSegmentNodeIds(
+        edgesAsGraphEdges(edges),
+        path.triggerNodeIds,
+        pulseActive
+      ),
+    [edges, path.triggerNodeIds, pulseActive]
+  )
+
+  useEffect(() => {
+    const endsAt = path.pulseEndsAt
+    if (endsAt == null) {
+      if (pulseTimerRef.current != null) {
+        clearTimeout(pulseTimerRef.current)
+        pulseTimerRef.current = null
+      }
+      pulseEndsAtRef.current = null
+      return
+    }
+    if (endsAt === pulseEndsAtRef.current) return
+    pulseEndsAtRef.current = endsAt
+    const delay = Math.max(0, endsAt - Date.now())
+    if (pulseTimerRef.current != null) clearTimeout(pulseTimerRef.current)
+    pulseTimerRef.current = setTimeout(() => {
+      pulseTimerRef.current = null
+      pulseEndsAtRef.current = null
+      dispatchCanvasCommand({ type: 'path/clearPathSession' })
+    }, delay)
+    return () => {
+      if (pulseTimerRef.current != null) {
+        clearTimeout(pulseTimerRef.current)
+        pulseTimerRef.current = null
+      }
+    }
+  }, [path.pulseEndsAt])
+
+  const addConnectionPathTrigger = useCallback((nodeId: string) => {
+    dispatchCanvasCommand({ type: 'path/addTrigger', payload: nodeId })
+  }, [])
+
+  const addConnectionPathPausedNode = useCallback((_nodeId: string) => {}, [])
+  const removeConnectionPathPausedNode = useCallback((_nodeId: string) => {}, [])
+
+  const addConnectionPathError = useCallback((nodeId: string) => {
+    dispatchCanvasCommand({
+      type: 'path/setError',
+      payload: { nodeId, error: true },
+    })
+  }, [])
+
+  const removeConnectionPathError = useCallback((nodeId: string) => {
+    dispatchCanvasCommand({
+      type: 'path/setError',
+      payload: { nodeId, error: false },
+    })
+  }, [])
+
+  return {
+    connectionPathUpdatingNodeIds: [],
+    connectionPathTriggerNodeIds: path.triggerNodeIds,
+    connectionPathPausedNodeIds: [],
+    connectionPathErrorNodeIds: path.errorNodeIds,
+    connectionPathNodeIds: pathNodeIds,
+    connectionPathPausedSegmentNodeIds: EMPTY_PAUSED_SEGMENT,
+    connectionPathActiveSegmentNodeIds: connectionPathActiveSegmentNodeIds,
+    startConnectionPathUpdate: () => {},
+    endConnectionPathUpdate: () => {},
+    addConnectionPathTrigger,
+    addConnectionPathPausedNode,
+    removeConnectionPathPausedNode,
+    addConnectionPathError,
+    removeConnectionPathError,
+  }
+}
+
+/**
+ * Path role for a node (trigger / updating / on-path) from the store.
+ * Use in node components so they only re-render when their path role changes.
+ */
+export function useConnectionPathRoleFromStore(nodeId: string | undefined): ConnectionPathRole {
+  return useCanvasStore((s) =>
+    nodeId != null ? selectPathRoleForNode(s, nodeId) : null
+  )
+}

frontend/src/app/canvas/useCanvasGraph.ts

@@ -0,0 +1,74 @@
+/**
+ * Hook for canvas graph state and persistence. Wraps useGraphStateWithHistory
+ * with initial graph from recollection storage (or example). Save is explicit via save().
+ */
+
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
+import { useGraphStateWithHistory } from '@/hooks/useGraphStateWithHistory'
+import { getInitialGraph } from '@/app/canvas/canvasGraphUtils'
+import { saveGraphToStorage, RECOLLECTION_VERSION } from '@/app/recollections/state/recollectionGraphStorage'
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+
+export type SaveStatus = 'saved' | 'unsaved' | 'saving'
+
+export type UseCanvasGraphResult = ReturnType<typeof useGraphStateWithHistory> & {
+  /** Persist current nodes/edges to storage. No-op when recollectionId is missing. */
+  save: () => void
+  /** For menubar: show "Unsaved changes" | "Saving…" | "All changes saved". */
+  saveStatus: SaveStatus
+}
+
+export function useCanvasGraph(recollectionId: string | undefined): UseCanvasGraphResult {
+  const initialGraph = useMemo(() => getInitialGraph(recollectionId), [recollectionId])
+  const result = useGraphStateWithHistory(initialGraph.nodes, initialGraph.edges)
+  const { nodes, edges } = result
+
+  const nodesRef = useRef(nodes)
+  const edgesRef = useRef(edges)
+  nodesRef.current = nodes
+  edgesRef.current = edges
+
+  const [isSaving, setIsSaving] = useState(false)
+  const [lastSavedSerialized, setLastSavedSerialized] = useState(() =>
+    JSON.stringify({ nodes: initialGraph.nodes, edges: initialGraph.edges })
+  )
+
+  const currentSerialized = useMemo(
+    () => JSON.stringify({ nodes, edges }),
+    [nodes, edges]
+  )
+  const isDirty = currentSerialized !== lastSavedSerialized
+  const saveStatus: SaveStatus = isSaving ? 'saving' : isDirty ? 'unsaved' : 'saved'
+
+  const save = useCallback(() => {
+    if (!recollectionId) return
+    const snapshot = JSON.stringify({
+      nodes: nodesRef.current,
+      edges: edgesRef.current,
+    })
+    setIsSaving(true)
+    saveGraphToStorage(recollectionId, {
+      version: RECOLLECTION_VERSION,
+      nodes: nodesRef.current,
+      edges: edgesRef.current,
+    })
+    const SAVING_DISPLAY_MS = 360
+    setTimeout(() => {
+      setLastSavedSerialized(snapshot)
+      setIsSaving(false)
+    }, SAVING_DISPLAY_MS)
+  }, [recollectionId])
+
+  // Auto-save after 5 seconds of inactivity when there are unsaved changes.
+  // Prevents data loss if the user closes the tab without pressing Ctrl+S.
+  const AUTO_SAVE_DELAY_MS = 5000
+  const saveRef = useRef(save)
+  saveRef.current = save
+  useEffect(() => {
+    if (!isDirty || !recollectionId) return
+    const timer = setTimeout(() => saveRef.current(), AUTO_SAVE_DELAY_MS)
+    return () => clearTimeout(timer)
+  }, [isDirty, recollectionId, currentSerialized])
+
+  return { ...result, save, saveStatus }
+}

frontend/src/app/kosmos/KosmosContext.tsx

@@ -0,0 +1,354 @@
+/**
+ * Platform context: recollections list and handlers for create/delete/rename/updateLastEdited/reorder/restore.
+ * Used by AppSidebar, RecollectionsPage, and canvas route.
+ */
+
+import React, { createContext, useCallback, useContext, useMemo, useState } from 'react'
+import type { Recollection } from './types'
+import { saveGraphToStorage, RECOLLECTION_VERSION } from '@/app/recollections/state/recollectionGraphStorage'
+
+const STORAGE_KEY = 'zui_platform_recollections'
+const ORDER_STORAGE_KEY = 'zui_platform_recollection_order'
+const RECENT_STORAGE_KEY = 'zui_platform_recent_recollection_ids'
+
+const LEGACY_STORAGE_KEY = 'zui_platform_emanations'
+const LEGACY_ORDER_STORAGE_KEY = 'zui_platform_emanation_order'
+const LEGACY_RECENT_STORAGE_KEY = 'zui_platform_recent_emanation_ids'
+const CANVAS_MINIMAP_KEY = 'zui_canvas_show_minimap'
+const AI_CONNECTION_KEY = 'zui_ai_connection'
+const RECENT_MAX = 5
+
+export type AiConnectionProvider = 'openai' | 'local'
+
+export type AiConnection = {
+  provider: AiConnectionProvider
+  baseURL: string
+  model: string
+  apiKey: string
+}
+
+const DEFAULT_AI_CONNECTION: AiConnection = {
+  provider: 'local',
+  baseURL: 'http://localhost:1234/v1',
+  model: 'local-model',
+  apiKey: '',
+}
+
+function loadAiConnection(): AiConnection {
+  try {
+    const raw = localStorage.getItem(AI_CONNECTION_KEY)
+    if (!raw) return DEFAULT_AI_CONNECTION
+    const parsed = JSON.parse(raw) as unknown
+    if (!parsed || typeof parsed !== 'object') return DEFAULT_AI_CONNECTION
+    const p = parsed as Record<string, unknown>
+    return {
+      provider: p.provider === 'openai' ? 'openai' : 'local',
+      baseURL: typeof p.baseURL === 'string' ? p.baseURL : DEFAULT_AI_CONNECTION.baseURL,
+      model: typeof p.model === 'string' ? p.model : DEFAULT_AI_CONNECTION.model,
+      apiKey: typeof p.apiKey === 'string' ? p.apiKey : '',
+    }
+  } catch {
+    return DEFAULT_AI_CONNECTION
+  }
+}
+
+function saveAiConnection(value: AiConnection) {
+  try {
+    localStorage.setItem(AI_CONNECTION_KEY, JSON.stringify(value))
+  } catch {}
+}
+
+function loadShowMinimap(): boolean {
+  try {
+    const raw = localStorage.getItem(CANVAS_MINIMAP_KEY)
+    if (raw === 'true') return true
+    if (raw === 'false') return false
+  } catch {}
+  return false
+}
+
+function saveShowMinimap(value: boolean) {
+  try {
+    localStorage.setItem(CANVAS_MINIMAP_KEY, JSON.stringify(value))
+  } catch {}
+}
+
+function loadOrder(): string[] {
+  try {
+    let raw = localStorage.getItem(ORDER_STORAGE_KEY)
+    if (!raw) {
+      const legacy = localStorage.getItem(LEGACY_ORDER_STORAGE_KEY)
+      if (legacy) {
+        localStorage.setItem(ORDER_STORAGE_KEY, legacy)
+        localStorage.removeItem(LEGACY_ORDER_STORAGE_KEY)
+        raw = legacy
+      } else return []
+    }
+    const parsed = JSON.parse(raw) as unknown
+    return Array.isArray(parsed) ? parsed.filter((id): id is string => typeof id === 'string') : []
+  } catch {
+    return []
+  }
+}
+
+function saveOrder(ids: string[]) {
+  localStorage.setItem(ORDER_STORAGE_KEY, JSON.stringify(ids))
+}
+
+function loadRecentIds(): string[] {
+  try {
+    let raw = localStorage.getItem(RECENT_STORAGE_KEY)
+    if (!raw) {
+      const legacy = localStorage.getItem(LEGACY_RECENT_STORAGE_KEY)
+      if (legacy) {
+        localStorage.setItem(RECENT_STORAGE_KEY, legacy)
+        localStorage.removeItem(LEGACY_RECENT_STORAGE_KEY)
+        raw = legacy
+      } else return []
+    }
+    const parsed = JSON.parse(raw) as unknown
+    return Array.isArray(parsed) ? parsed.filter((id): id is string => typeof id === 'string').slice(0, RECENT_MAX) : []
+  } catch {
+    return []
+  }
+}
+
+function saveRecentIds(ids: string[]) {
+  localStorage.setItem(RECENT_STORAGE_KEY, JSON.stringify(ids))
+}
+
+function loadRecollections(): Recollection[] {
+  try {
+    let raw = localStorage.getItem(STORAGE_KEY)
+    if (!raw) {
+      const legacy = localStorage.getItem(LEGACY_STORAGE_KEY)
+      if (legacy) {
+        localStorage.setItem(STORAGE_KEY, legacy)
+        localStorage.removeItem(LEGACY_STORAGE_KEY)
+        raw = legacy
+      } else return []
+    }
+    const parsed = JSON.parse(raw) as unknown
+    if (!Array.isArray(parsed)) return []
+    return parsed
+      .filter(
+        (p): p is Recollection =>
+          p &&
+          typeof p === 'object' &&
+          typeof (p as Recollection).id === 'string' &&
+          typeof (p as Recollection).name === 'string' &&
+          typeof (p as Recollection).iconId === 'string' &&
+          typeof (p as Recollection).createdAt === 'number'
+      )
+      .map((p) => ({
+        ...p,
+        lastEditedAt: typeof (p as Recollection).lastEditedAt === 'number' ? (p as Recollection).lastEditedAt : p.createdAt,
+      }))
+  } catch {
+    return []
+  }
+}
+
+function saveRecollections(recollections: Recollection[]) {
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(recollections))
+}
+
+export type GraphSnapshot = { nodes: unknown[]; edges: unknown[] }
+
+/** Recollections sorted by recollectionOrder, then by lastEditedAt desc for any not in order */
+export function sortRecollectionsByOrder(recollections: Recollection[], order: string[]): Recollection[] {
+  const byId = new Map(recollections.map((p) => [p.id, p]))
+  const ordered: Recollection[] = []
+  const seen = new Set<string>()
+  for (const id of order) {
+    const p = byId.get(id)
+    if (p) {
+      ordered.push(p)
+      seen.add(id)
+    }
+  }
+  const rest = recollections
+    .filter((p) => !seen.has(p.id))
+    .sort((a, b) => (b.lastEditedAt ?? b.createdAt) - (a.lastEditedAt ?? a.createdAt))
+  return [...ordered, ...rest]
+}
+
+export type KosmosContextValue = {
+  recollections: Recollection[]
+  recollectionOrder: string[]
+  /** Recollections in display order (sidebar order, then lastEditedAt) */
+  orderedRecollections: Recollection[]
+  /** Last RECENT_MAX accessed recollection IDs (most recent first) */
+  recentRecollectionIds: string[]
+  recordRecollectionAccess: (id: string) => void
+  persist: (next: Recollection[]) => void
+  createRecollection: (recollection: Recollection) => void
+  deleteRecollection: (id: string) => void
+  renameRecollection: (id: string, name: string) => void
+  updateLastEdited: (id: string) => void
+  reorderRecollections: (orderedIds: string[]) => void
+  restoreRecollection: (recollection: Recollection, graphSnapshot: GraphSnapshot | null) => void
+  /** Canvas: show React Flow minimap (persisted) */
+  showMinimap: boolean
+  setShowMinimap: (value: boolean) => void
+  /** Agent node: AI connection (persisted). Sent to backend when running agent. */
+  aiConnection: AiConnection
+  setAiConnection: (value: AiConnection) => void
+}
+
+const KosmosContext = createContext<KosmosContextValue | null>(null)
+
+export function KosmosProvider({ children }: { children: React.ReactNode }) {
+  const [recollections, setRecollections] = useState<Recollection[]>(loadRecollections)
+  const [recollectionOrder, setRecollectionOrder] = useState<string[]>(loadOrder)
+  const [recentRecollectionIds, setRecentRecollectionIds] = useState<string[]>(loadRecentIds)
+  const [showMinimap, setShowMinimapState] = useState<boolean>(loadShowMinimap)
+  const [aiConnection, setAiConnectionState] = useState<AiConnection>(loadAiConnection)
+
+  const setShowMinimap = useCallback((value: boolean) => {
+    setShowMinimapState(value)
+    saveShowMinimap(value)
+  }, [])
+
+  const setAiConnection = useCallback((value: AiConnection) => {
+    setAiConnectionState(value)
+    saveAiConnection(value)
+  }, [])
+
+  const persist = useCallback((next: Recollection[]) => {
+    setRecollections(next)
+    saveRecollections(next)
+  }, [])
+
+  const createRecollection = useCallback(
+    (recollection: Recollection) => {
+      const withEdited = { ...recollection, lastEditedAt: recollection.createdAt }
+      persist([...recollections, withEdited])
+      setRecollectionOrder((prev) => {
+        const next = prev.includes(recollection.id) ? prev : [recollection.id, ...prev]
+        saveOrder(next)
+        return next
+      })
+    },
+    [recollections, persist]
+  )
+
+  const deleteRecollection = useCallback(
+    (id: string) => {
+      const next = recollections.filter((p) => p.id !== id)
+      persist(next)
+      setRecollectionOrder((prev) => {
+        const nextOrder = prev.filter((oid) => oid !== id)
+        saveOrder(nextOrder)
+        return nextOrder
+      })
+      setRecentRecollectionIds((prev) => {
+        const next = prev.filter((oid) => oid !== id)
+        saveRecentIds(next)
+        return next
+      })
+    },
+    [recollections, persist]
+  )
+
+  const renameRecollection = useCallback(
+    (id: string, name: string) => {
+      const next = recollections.map((p) => (p.id === id ? { ...p, name } : p))
+      persist(next)
+    },
+    [recollections, persist]
+  )
+
+  const updateLastEdited = useCallback(
+    (id: string) => {
+      const now = Date.now()
+      const next = recollections.map((p) => (p.id === id ? { ...p, lastEditedAt: now } : p))
+      persist(next)
+    },
+    [recollections, persist]
+  )
+
+  const reorderRecollections = useCallback((orderedIds: string[]) => {
+    setRecollectionOrder(orderedIds)
+    saveOrder(orderedIds)
+  }, [])
+
+  const recordRecollectionAccess = useCallback((id: string) => {
+    setRecentRecollectionIds((prev) => {
+      const next = [id, ...prev.filter((x) => x !== id)].slice(0, RECENT_MAX)
+      saveRecentIds(next)
+      return next
+    })
+  }, [])
+
+  const restoreRecollection = useCallback(
+    (recollection: Recollection, graphSnapshot: GraphSnapshot | null) => {
+      persist([...recollections, recollection])
+      setRecollectionOrder((prev) => {
+        const next = prev.includes(recollection.id) ? prev : [recollection.id, ...prev]
+        saveOrder(next)
+        return next
+      })
+      if (graphSnapshot) {
+        saveGraphToStorage(recollection.id, {
+          version: RECOLLECTION_VERSION,
+          nodes: graphSnapshot.nodes,
+          edges: graphSnapshot.edges,
+        })
+      }
+    },
+    [recollections, persist]
+  )
+
+  const orderedRecollections = useMemo(
+    () => sortRecollectionsByOrder(recollections, recollectionOrder),
+    [recollections, recollectionOrder]
+  )
+
+  const value: KosmosContextValue = useMemo(
+    () => ({
+      recollections,
+      recollectionOrder,
+      orderedRecollections,
+      recentRecollectionIds,
+      recordRecollectionAccess,
+      persist,
+      createRecollection,
+      deleteRecollection,
+      renameRecollection,
+      updateLastEdited,
+      reorderRecollections,
+      restoreRecollection,
+      showMinimap,
+      setShowMinimap,
+      aiConnection,
+      setAiConnection,
+    }),
+    [
+      recollections,
+      recollectionOrder,
+      orderedRecollections,
+      recentRecollectionIds,
+      recordRecollectionAccess,
+      persist,
+      createRecollection,
+      deleteRecollection,
+      renameRecollection,
+      updateLastEdited,
+      reorderRecollections,
+      restoreRecollection,
+      showMinimap,
+      setShowMinimap,
+      aiConnection,
+      setAiConnection,
+    ]
+  )
+
+  return <KosmosContext.Provider value={value}>{children}</KosmosContext.Provider>
+}
+
+export function usePlatform() {
+  const ctx = useContext(KosmosContext)
+  if (!ctx) throw new Error('usePlatform must be used within PlatformProvider')
+  return ctx
+}

frontend/src/app/kosmos/KosmosPage.tsx

@@ -0,0 +1,40 @@
+/**
+ * Platform: main layout with sidebar and header. Renders child routes (recollections list or canvas) via Outlet.
+ */
+
+import React, { useEffect, useState } from 'react'
+import { Outlet, useParams } from 'react-router-dom'
+import { SidebarProvider } from '@/components/ui/sidebar'
+import { KosmosProvider, usePlatform } from './KosmosContext'
+import { KosmosSidebar } from './KosmosSidebar'
+
+function KosmosLayoutInner() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { recordRecollectionAccess } = usePlatform()
+  const [sidebarOpen, setSidebarOpen] = useState(true)
+
+  useEffect(() => {
+    if (recollectionId) recordRecollectionAccess(recollectionId)
+  }, [recollectionId, recordRecollectionAccess])
+
+  const showSidebar = !recollectionId
+
+  return (
+    <SidebarProvider open={sidebarOpen} onOpenChange={setSidebarOpen}>
+      {showSidebar && <KosmosSidebar />}
+      <div className="relative flex h-dvh min-h-0 w-full flex-1 flex-col overflow-hidden bg-background">
+        <div className="flex min-h-0 flex-1 flex-col overflow-hidden">
+          <Outlet />
+        </div>
+      </div>
+    </SidebarProvider>
+  )
+}
+
+export function KosmosPage() {
+  return (
+    <KosmosProvider>
+      <KosmosLayoutInner />
+    </KosmosProvider>
+  )
+}

frontend/src/app/kosmos/KosmosSidebar.tsx

@@ -0,0 +1,198 @@
+/**
+ * Platform sidebar: Recollections, Recently used, New recollection.
+ */
+
+import React, { useCallback, useMemo } from 'react'
+import { Link, useNavigate, useParams, useLocation } from 'react-router-dom'
+import {
+  Sidebar,
+  SidebarContent,
+  SidebarFooter,
+  SidebarGroup,
+  SidebarGroupLabel,
+  SidebarHeader,
+  SidebarMenu,
+  SidebarMenuButton,
+  SidebarMenuItem,
+  SidebarRail,
+  SidebarTrigger,
+} from '@/components/ui/sidebar'
+import { Plus, Settings } from 'lucide-react'
+import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip'
+import { useSidebar } from '@/components/ui/sidebar'
+import { usePlatform } from './KosmosContext'
+import { getRecollectionIcon } from '@/lib/iconMap'
+import { RecollectionsIcon } from '@/lib/icons'
+import { NewRecollectionDialog } from './NewRecollectionDialog'
+import { SettingsDialog } from './SettingsDialog'
+import type { Recollection } from './types'
+
+export function KosmosSidebar() {
+  const { state, setOpen } = useSidebar()
+  const isCollapsed = state === 'collapsed'
+  const { orderedRecollections, createRecollection, recentRecollectionIds } = usePlatform()
+  const recentRecollections = useMemo(() => {
+    const byId = new Map(orderedRecollections.map((p) => [p.id, p]))
+    return recentRecollectionIds.map((id) => byId.get(id)).filter((p): p is Recollection => p != null)
+  }, [orderedRecollections, recentRecollectionIds])
+  const navigate = useNavigate()
+  const location = useLocation()
+  const { recollectionId: selectedRecollectionId } = useParams<{ recollectionId: string }>()
+
+  const handleCreateRecollection = useCallback(
+    (recollection: Parameters<typeof createRecollection>[0]) => {
+      createRecollection(recollection)
+      navigate(`/recollections/${recollection.id}`)
+    },
+    [createRecollection, navigate]
+  )
+
+  return (
+    <>
+      <Sidebar collapsible="icon" className="relative">
+        {isCollapsed && (
+          <button
+            type="button"
+            className="absolute inset-0 z-0 cursor-pointer border-0 bg-transparent p-0 outline-none"
+            onClick={() => setOpen(true)}
+            aria-label="Expand sidebar"
+          />
+        )}
+        <SidebarHeader className="relative z-10 flex flex-row items-center gap-2">
+          <SidebarMenu className="flex-1 min-w-0">
+            <SidebarMenuItem>
+              {isCollapsed ? (
+                <Tooltip>
+                  <TooltipTrigger asChild>
+                    <SidebarMenuButton
+                      size="lg"
+                      className="font-semibold font-serif"
+                      onClick={(e) => {
+                        e.preventDefault()
+                        e.stopPropagation()
+                        setOpen(true)
+                      }}
+                    >
+                      <span className="flex size-8 min-w-8 items-center justify-center rounded-lg bg-sidebar-primary text-sidebar-primary-foreground dark:bg-white dark:text-black">
+                        <span
+                          className="size-6 shrink-0 rounded-[2px] opacity-90"
+                          style={{
+                            maskImage: 'url(/app-icon.svg)',
+                            maskRepeat: 'no-repeat',
+                            maskPosition: 'center',
+                            maskSize: 'contain',
+                            WebkitMaskImage: 'url(/app-icon.svg)',
+                            WebkitMaskRepeat: 'no-repeat',
+                            WebkitMaskPosition: 'center',
+                            WebkitMaskSize: 'contain',
+                            backgroundColor: 'currentColor',
+                          }}
+                          aria-hidden
+                        />
+                      </span>
+                      <span className="font-serif group-data-[collapsible=icon]:hidden uppercase tracking-wide">ZOË</span>
+                    </SidebarMenuButton>
+                  </TooltipTrigger>
+                  <TooltipContent side="right">Click to expand sidebar</TooltipContent>
+                </Tooltip>
+              ) : (
+                <SidebarMenuButton asChild size="lg" tooltip="Zoë" className="font-semibold font-serif">
+                  <Link to="/recollections">
+                    <span className="flex size-8 min-w-8 items-center justify-center rounded-lg dark:bg-white dark:text-black">
+                      <span
+                        className="size-6 shrink-0 rounded-[2px] opacity-90"
+                        style={{
+                          maskImage: 'url(/app-icon.svg)',
+                          maskRepeat: 'no-repeat',
+                          maskPosition: 'center',
+                          maskSize: 'contain',
+                          WebkitMaskImage: 'url(/app-icon.svg)',
+                          WebkitMaskRepeat: 'no-repeat',
+                          WebkitMaskPosition: 'center',
+                          WebkitMaskSize: 'contain',
+                          backgroundColor: 'currentColor',
+                        }}
+                        aria-hidden
+                      />
+                    </span>
+                    <span className="font-serif group-data-[collapsible=icon]:hidden uppercase tracking-wide">ZOË</span>
+                  </Link>
+                </SidebarMenuButton>
+              )}
+            </SidebarMenuItem>
+          </SidebarMenu>
+          {!isCollapsed && <SidebarTrigger className="ml-auto shrink-0" />}
+        </SidebarHeader>
+        <SidebarContent
+          className="relative z-10"
+          onClick={isCollapsed ? (e) => { if ((e.target as HTMLElement).closest('button') || (e.target as HTMLElement).closest('a')) return; setOpen(true) } : undefined}
+        >
+          <SidebarGroup>
+            <SidebarMenu>
+              <SidebarMenuItem>
+                <SidebarMenuButton asChild tooltip="Recollections" isActive={location.pathname === '/recollections' && !selectedRecollectionId}>
+                  <Link to="/recollections">
+                    <RecollectionsIcon className="size-4 shrink-0" />
+                    <span>Recollections</span>
+                  </Link>
+                </SidebarMenuButton>
+              </SidebarMenuItem>
+            </SidebarMenu>
+          </SidebarGroup>
+          {recentRecollections.length > 0 && (
+            <SidebarGroup>
+              <SidebarGroupLabel className="group-data-[collapsible=icon]:hidden">Recently used</SidebarGroupLabel>
+              <SidebarMenu>
+                {recentRecollections.map((recollection) => {
+                  const Icon = getRecollectionIcon(recollection.iconId)
+                  const isActive = selectedRecollectionId === recollection.id
+                  return (
+                    <SidebarMenuItem key={recollection.id}>
+                      <SidebarMenuButton asChild tooltip={recollection.name} isActive={isActive}>
+                        <Link to={`/recollections/${recollection.id}`}>
+                          <Icon className="size-4" />
+                          <span>{recollection.name}</span>
+                        </Link>
+                      </SidebarMenuButton>
+                    </SidebarMenuItem>
+                  )
+                })}
+              </SidebarMenu>
+            </SidebarGroup>
+          )}
+          <SidebarGroup>
+            <SidebarMenu>
+              <SidebarMenuItem>
+                <NewRecollectionDialog
+                  onCreate={handleCreateRecollection}
+                  existingNames={orderedRecollections.map((p) => p.name)}
+                  trigger={
+                    <SidebarMenuButton className="text-sidebar-foreground/70 w-full cursor-pointer">
+                      <Plus className="size-4" />
+                      <span>{orderedRecollections.length === 0 ? 'Create your first recollection' : 'New recollection'}</span>
+                    </SidebarMenuButton>
+                  }
+                />
+              </SidebarMenuItem>
+            </SidebarMenu>
+          </SidebarGroup>
+        </SidebarContent>
+        <SidebarFooter className="relative z-10">
+          <SidebarMenu>
+            <SidebarMenuItem>
+              <SettingsDialog
+                trigger={
+                  <SidebarMenuButton tooltip="Settings" className="w-full">
+                    <Settings className="size-4" />
+                    <span className="group-data-[collapsible=icon]:hidden">Settings</span>
+                  </SidebarMenuButton>
+                }
+              />
+            </SidebarMenuItem>
+          </SidebarMenu>
+        </SidebarFooter>
+        <SidebarRail className="relative z-10" />
+      </Sidebar>
+    </>
+  )
+}

frontend/src/app/kosmos/NewRecollectionDialog.tsx

@@ -0,0 +1,118 @@
+/**
+ * Dialog to create a new recollection: name + icon.
+ */
+
+import React, { useState } from 'react'
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+  DialogTrigger,
+} from '@/components/ui/dialog'
+import { Button } from '@/components/ui/button'
+import { Input } from '@/components/ui/input'
+import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select'
+import { Plus } from 'lucide-react'
+import { RECOLLECTION_ICON_IDS, type Recollection, type RecollectionIconId } from './types'
+import { getRecollectionIcon } from '@/lib/iconMap'
+
+type NewRecollectionDialogProps = {
+  onCreate: (recollection: Recollection) => void
+  trigger?: React.ReactNode
+  /** Other recollection names to check for duplicates (case-insensitive warning only) */
+  existingNames?: string[]
+}
+
+export function NewRecollectionDialog({ onCreate, trigger, existingNames = [] }: NewRecollectionDialogProps) {
+  const [open, setOpen] = useState(false)
+  const [name, setName] = useState('')
+  const [iconId, setIconId] = useState<RecollectionIconId>('cat')
+
+  const trimmed = name.trim()
+  const isDuplicate = trimmed.length > 0 && existingNames.some((n) => n.toLowerCase() === trimmed.toLowerCase())
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault()
+    if (!trimmed) return
+    const recollection: Recollection = {
+      id: `recollection_${Date.now()}`,
+      name: trimmed,
+      iconId,
+      createdAt: Date.now(),
+    }
+    onCreate(recollection)
+    setName('')
+    setIconId('cat')
+    setOpen(false)
+  }
+
+  return (
+    <Dialog open={open} onOpenChange={setOpen}>
+      <DialogTrigger asChild>
+        {trigger ?? (
+          <Button variant="outline" size="sm" className="w-full justify-start gap-2">
+            <Plus className="size-4" />
+            New recollection
+          </Button>
+        )}
+      </DialogTrigger>
+      <DialogContent className="sm:max-w-md">
+        <form onSubmit={handleSubmit}>
+          <DialogHeader>
+            <DialogTitle>New recollection</DialogTitle>
+            <DialogDescription>Create a recollection to start editing a graph canvas.</DialogDescription>
+          </DialogHeader>
+          <div className="grid gap-4 py-4">
+            <div className="grid gap-2">
+              <label htmlFor="recollection-name" className="text-sm font-medium">
+                Name
+              </label>
+              <Input
+                id="recollection-name"
+                value={name}
+                onChange={(e) => setName(e.target.value)}
+                placeholder="My recollection"
+                autoFocus
+              />
+              {isDuplicate && (
+                <p className="text-xs text-amber-600 dark:text-amber-500">A recollection with this name already exists.</p>
+              )}
+            </div>
+            <div className="grid gap-2">
+              <label className="text-sm font-medium">Icon</label>
+              <Select value={iconId} onValueChange={(v) => setIconId(v as RecollectionIconId)}>
+                <SelectTrigger>
+                  <SelectValue />
+                </SelectTrigger>
+                <SelectContent>
+                  {RECOLLECTION_ICON_IDS.map((id) => {
+                    const Icon = getRecollectionIcon(id)
+                    return (
+                      <SelectItem key={id} value={id}>
+                        <span className="flex items-center gap-2">
+                          <Icon className="size-4" />
+                          {id}
+                        </span>
+                      </SelectItem>
+                    )
+                  })}
+                </SelectContent>
+              </Select>
+            </div>
+          </div>
+          <DialogFooter>
+            <Button type="button" variant="outline" onClick={() => setOpen(false)}>
+              Cancel
+            </Button>
+            <Button type="submit" disabled={!name.trim()}>
+              Create
+            </Button>
+          </DialogFooter>
+        </form>
+      </DialogContent>
+    </Dialog>
+  )
+}

frontend/src/app/kosmos/SettingsDialog.tsx

@@ -0,0 +1,194 @@
+/**
+ * Settings dialog with sidebar-style nav (Appearance, AI). Reference: shadcn sidebar-13.
+ */
+
+import React, { useCallback, useState } from 'react'
+import {
+  Dialog,
+  DialogContent,
+  DialogHeader,
+  DialogTitle,
+  DialogTrigger,
+} from '@/components/ui/dialog'
+import { Button } from '@/components/ui/button'
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from '@/components/ui/select'
+import { Switch } from '@/components/ui/switch'
+import { Input } from '@/components/ui/input'
+import { useTheme } from '@/lib/themeContext'
+import type { Theme } from '@/lib/themeContext'
+import { usePlatform } from './KosmosContext'
+import type { AiConnection, AiConnectionProvider } from './KosmosContext'
+import { Sun, Sparkles } from 'lucide-react'
+
+type SettingsSection = 'appearance' | 'ai'
+
+export function SettingsDialog({
+  trigger,
+}: {
+  trigger: React.ReactNode
+}) {
+  const [open, setOpen] = useState(false)
+  const [section, setSection] = useState<SettingsSection>('appearance')
+  const { theme, setTheme } = useTheme()
+  const { showMinimap, setShowMinimap, aiConnection, setAiConnection } = usePlatform()
+
+  const updateAiConnection = useCallback(
+    (partial: Partial<AiConnection>) => {
+      setAiConnection({ ...aiConnection, ...partial })
+    },
+    [aiConnection, setAiConnection]
+  )
+
+  return (
+    <Dialog open={open} onOpenChange={setOpen}>
+      <DialogTrigger asChild>{trigger}</DialogTrigger>
+      <DialogContent
+        className="flex h-[min(85vh,28rem)] max-w-2xl p-0 gap-0 overflow-hidden"
+        aria-describedby={undefined}
+      >
+        <DialogHeader className="sr-only">
+          <DialogTitle>Settings</DialogTitle>
+        </DialogHeader>
+        <div className="flex flex-1 min-h-0 w-full">
+          <nav
+            className="flex w-44 shrink-0 flex-col gap-1 border-r bg-muted/30 p-2"
+            aria-label="Settings sections"
+          >
+            <div className="px-2 py-1.5 text-xs font-medium text-muted-foreground">
+              Settings
+            </div>
+            <Button
+              variant={section === 'appearance' ? 'secondary' : 'ghost'}
+              size="sm"
+              className="justify-start gap-2"
+              onClick={() => setSection('appearance')}
+            >
+              <Sun className="size-4 shrink-0 opacity-70" />
+              Appearance
+            </Button>
+            <Button
+              variant={section === 'ai' ? 'secondary' : 'ghost'}
+              size="sm"
+              className="justify-start gap-2"
+              onClick={() => setSection('ai')}
+            >
+              <Sparkles className="size-4 shrink-0 opacity-70" />
+              AI
+            </Button>
+          </nav>
+          <div className="flex-1 min-h-0 overflow-auto p-4">
+            {section === 'appearance' && (
+              <div className="space-y-6">
+                <h3 className="text-sm font-medium text-muted-foreground">Appearance</h3>
+                <div className="grid grid-cols-1 gap-4 sm:grid-cols-[minmax(0,1fr)_auto] sm:items-center">
+                  <label htmlFor="settings-theme" className="text-sm font-medium">
+                    Theme
+                  </label>
+                  <Select value={theme} onValueChange={(v) => setTheme(v as Theme)}>
+                    <SelectTrigger id="settings-theme" className="w-full min-w-[8rem] sm:w-40">
+                      <SelectValue placeholder="Theme" />
+                    </SelectTrigger>
+                    <SelectContent>
+                      <SelectItem value="light">Light</SelectItem>
+                      <SelectItem value="dark">Dark</SelectItem>
+                    </SelectContent>
+                  </Select>
+                </div>
+                <div className="space-y-3 pt-2 border-t">
+                  <h4 className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
+                    Canvas
+                  </h4>
+                  <div className="grid grid-cols-1 gap-4 sm:grid-cols-[minmax(0,1fr)_auto] sm:items-center">
+                    <label htmlFor="settings-minimap" className="text-sm font-medium">
+                      Minimap
+                    </label>
+                    <Switch
+                      id="settings-minimap"
+                      checked={showMinimap}
+                      onCheckedChange={setShowMinimap}
+                    />
+                  </div>
+                </div>
+              </div>
+            )}
+            {section === 'ai' && (
+              <div className="space-y-6">
+                <h3 className="text-sm font-medium text-muted-foreground">AI connection</h3>
+                <p className="text-xs text-muted-foreground">
+                  Used by the Agent node. Choose OpenAI or a local server (e.g. LM Studio).
+                </p>
+                <div className="space-y-4">
+                  <div className="grid grid-cols-1 gap-2 sm:grid-cols-[minmax(0,1fr)_auto] sm:items-center">
+                    <label htmlFor="settings-ai-provider" className="text-sm font-medium">
+                      Provider
+                    </label>
+                    <Select
+                      value={aiConnection.provider}
+                      onValueChange={(v) => updateAiConnection({ provider: v as AiConnectionProvider })}
+                    >
+                      <SelectTrigger id="settings-ai-provider" className="w-full min-w-[10rem] sm:w-48">
+                        <SelectValue />
+                      </SelectTrigger>
+                      <SelectContent>
+                        <SelectItem value="local">Local (LM Studio, Ollama, etc.)</SelectItem>
+                        <SelectItem value="openai">OpenAI</SelectItem>
+                      </SelectContent>
+                    </Select>
+                  </div>
+                  {aiConnection.provider === 'local' && (
+                    <div className="grid grid-cols-1 gap-2 sm:grid-cols-[minmax(0,1fr)_1fr] sm:items-center">
+                      <label htmlFor="settings-ai-baseurl" className="text-sm font-medium">
+                        Base URL
+                      </label>
+                      <Input
+                        id="settings-ai-baseurl"
+                        type="url"
+                        placeholder="http://localhost:1234/v1"
+                        value={aiConnection.baseURL}
+                        onChange={(e) => updateAiConnection({ baseURL: e.target.value })}
+                        className="font-mono text-xs"
+                      />
+                    </div>
+                  )}
+                  <div className="grid grid-cols-1 gap-2 sm:grid-cols-[minmax(0,1fr)_1fr] sm:items-center">
+                    <label htmlFor="settings-ai-model" className="text-sm font-medium">
+                      Model
+                    </label>
+                    <Input
+                      id="settings-ai-model"
+                      type="text"
+                      placeholder={aiConnection.provider === 'local' ? 'local-model' : 'gpt-4o-mini'}
+                      value={aiConnection.model}
+                      onChange={(e) => updateAiConnection({ model: e.target.value })}
+                      className="font-mono text-xs"
+                    />
+                  </div>
+                  <div className="grid grid-cols-1 gap-2 sm:grid-cols-[minmax(0,1fr)_1fr] sm:items-center">
+                    <label htmlFor="settings-ai-apikey" className="text-sm font-medium">
+                      API key
+                    </label>
+                    <Input
+                      id="settings-ai-apikey"
+                      type="password"
+                      autoComplete="off"
+                      placeholder={aiConnection.provider === 'openai' ? 'sk-...' : 'Optional for local'}
+                      value={aiConnection.apiKey}
+                      onChange={(e) => updateAiConnection({ apiKey: e.target.value })}
+                      className="font-mono text-xs"
+                    />
+                  </div>
+                </div>
+              </div>
+            )}
+          </div>
+        </div>
+      </DialogContent>
+    </Dialog>
+  )
+}

frontend/src/app/kosmos/types.ts

@@ -0,0 +1,33 @@
+/**
+ * Platform types: recollections and sidebar state.
+ */
+
+import type { LucideIcon } from 'lucide-react'
+
+export type Recollection = {
+  id: string
+  name: string
+  /** Icon identifier: key of RECOLLECTION_ICONS map */
+  iconId: string
+  createdAt: number
+  /** Last time the recollection was opened/edited; used for sorting. Defaults to createdAt if missing. */
+  lastEditedAt?: number
+}
+
+/** Recollection icon ids: Lucide "Animals" category only */
+export const RECOLLECTION_ICON_IDS = [
+  'bird',
+  'bug',
+  'cat',
+  'dog',
+  'fish',
+  'rat',
+  'rabbit',
+  'squirrel',
+  'turtle',
+  'snail',
+  'shrimp',
+  'egg'
+] as const
+
+export type RecollectionIconId = (typeof RECOLLECTION_ICON_IDS)[number]

frontend/src/app/recollections/RecollectionLayout.tsx

@@ -0,0 +1,65 @@
+/**
+ * Layout for a single recollection: shared menubar and nested routes for Logos / Katalogos / Flux.
+ */
+
+import React, { useEffect } from 'react'
+import { Outlet, useParams, useNavigate } from 'react-router-dom'
+import { toast } from 'sonner'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import { RecollectionActionsProvider } from './layout/RecollectionActionsContext'
+import { RecollectionSidebarProvider } from './layout/RecollectionSidebarContext'
+import { RecollectionMenubar } from './layout/RecollectionMenubar'
+import { RecollectionSidebar } from './layout/RecollectionSidebar'
+
+export function RecollectionLayout() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const navigate = useNavigate()
+  const { recollections, recordRecollectionAccess } = usePlatform()
+
+  useEffect(() => {
+    if (recollectionId) recordRecollectionAccess(recollectionId)
+  }, [recollectionId, recordRecollectionAccess])
+
+  const recollection = recollectionId ? recollections.find((p) => p.id === recollectionId) : null
+
+  useEffect(() => {
+    if (!recollectionId) return
+    if (recollection) return
+    toast.error('Recollection not found')
+    navigate('/recollections', { replace: true })
+  }, [recollectionId, recollection, navigate])
+
+  // Keyboard shortcut: Escape to go back to recollections list
+  useEffect(() => {
+    if (!recollection) return
+    const onKeyDown = (ev: KeyboardEvent) => {
+      if (ev.key !== 'Escape') return
+      if ((ev.target as HTMLElement)?.closest('input, textarea, [contenteditable="true"]')) return
+      ev.preventDefault()
+      navigate('/recollections')
+    }
+    window.addEventListener('keydown', onKeyDown, true)
+    return () => window.removeEventListener('keydown', onKeyDown, true)
+  }, [recollection, navigate])
+
+  if (!recollectionId) return null
+  if (!recollection) {
+    return null
+  }
+
+  return (
+    <RecollectionActionsProvider>
+      <RecollectionSidebarProvider>
+        <div className="flex min-h-0 flex-1 flex-col">
+          <RecollectionMenubar />
+          <div className="flex min-h-0 flex-1 flex-row overflow-hidden">
+            <RecollectionSidebar />
+            <div className="flex min-w-0 flex-1 flex-col overflow-hidden">
+              <Outlet />
+            </div>
+          </div>
+        </div>
+      </RecollectionSidebarProvider>
+    </RecollectionActionsProvider>
+  )
+}

frontend/src/app/recollections/flux/FluxRoute.tsx

@@ -0,0 +1,31 @@
+/**
+ * Flux route: renders the graph canvas (CanvasPage) for the current recollection.
+ * Supports optional focusNode query param to center on a specific node.
+ */
+
+import React, { useEffect, useRef } from 'react'
+import { useParams, useSearchParams } from 'react-router-dom'
+import { CanvasPage } from '@/app/canvas/CanvasPage'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+
+export function FluxRoute() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const [searchParams] = useSearchParams()
+  const { updateLastEdited } = usePlatform()
+  const updateLastEditedRef = useRef(updateLastEdited)
+  updateLastEditedRef.current = updateLastEdited
+
+  useEffect(() => {
+    if (recollectionId) updateLastEditedRef.current(recollectionId)
+  }, [recollectionId])
+
+  const focusNodeId = searchParams.get('focusNode') ?? undefined
+
+  if (!recollectionId) return null
+
+  return (
+    <div className="flex h-full min-h-0 flex-1 flex-col overflow-hidden">
+      <CanvasPage key={recollectionId} recollectionId={recollectionId} focusNodeId={focusNodeId} />
+    </div>
+  )
+}

frontend/src/app/recollections/katalogos/KatalogosPage.tsx

@@ -0,0 +1,127 @@
+/**
+ * Katalogos page: third view for a recollection.
+ * Shows live \"Artifacts\" from Flux rendering nodes in a card grid.
+ */
+
+import React, { useMemo } from 'react'
+import { useNavigate, useParams } from 'react-router-dom'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import { getRenderOutputCache, formatTimeSinceLastUpdate } from '../state/recollectionStore'
+import { Button } from '@/components/ui/button'
+
+export function KatalogosPage() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { recollections } = usePlatform()
+  const navigate = useNavigate()
+
+  const recollection = recollectionId ? recollections.find((p) => p.id === recollectionId) : null
+  const title = recollection?.name ?? 'Untitled'
+
+  const artifacts = useMemo(
+    () => (recollectionId ? getRenderOutputCache(recollectionId) : []),
+    [recollectionId]
+  )
+
+  const handleViewInFlux = (nodeId: string) => {
+    if (!recollectionId) return
+    navigate(`/recollections/${recollectionId}/flux?focusNode=${encodeURIComponent(nodeId)}`)
+  }
+
+  return (
+    <div className="flex h-full min-h-0 flex-1 flex-col overflow-auto bg-background">
+      <div className="mx-auto w-full max-w-5xl p-4">
+        <h1 className="mb-2 truncate font-serif text-2xl font-semibold tracking-tight text-foreground">
+          {title}
+        </h1>
+        <p className="mb-6 text-sm text-muted-foreground">
+          Katalogos · Live artifacts produced by Flux rendering nodes for this recollection.
+        </p>
+        {artifacts.length === 0 ? (
+          <div className="rounded-lg border border-dashed border-muted-foreground/30 bg-muted/10 p-4 text-sm text-muted-foreground">
+            No artifacts yet. In Flux, run a graph with a rendering node; its output will be cached as an artifact and
+            appear here, as well as in Logos blocks that insert artifacts.
+          </div>
+        ) : (
+          <div className="grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-3">
+            {artifacts.map((artifact) => {
+              const label = artifact.label || artifact.nodeId
+              const isImage =
+                artifact.type === 'image' ||
+                Boolean(artifact.content?.trim() && /<svg[\\s>]/i.test(artifact.content.trim()))
+              const imageSrc =
+                isImage && artifact.content
+                  ? artifact.content.startsWith('data:')
+                    ? artifact.content
+                    : `data:image/svg+xml;utf8,${encodeURIComponent(artifact.content)}`
+                  : null
+
+              return (
+                <div
+                  key={artifact.nodeId}
+                  className="flex h-full flex-col rounded-lg border border-border bg-card text-card-foreground shadow-sm"
+                >
+                  <div className="flex items-center justify-between gap-2 border-b border-border/60 px-3 py-2">
+                    <div className="min-w-0">
+                      <p className="truncate text-sm font-medium">{label}</p>
+                      <p className="truncate text-xs text-muted-foreground">Node: {artifact.nodeId}</p>
+                    </div>
+                    <span className="inline-flex items-center gap-1 rounded-full bg-emerald-500/10 px-2 py-0.5 text-[11px] font-medium uppercase tracking-wide text-emerald-500">
+                      <span className="h-1.5 w-1.5 rounded-full bg-emerald-500" />
+                      Live
+                    </span>
+                  </div>
+                  <div className="flex flex-1 flex-col gap-2 px-3 py-3">
+                    {isImage && imageSrc ? (
+                      <div className="flex min-h-[120px] items-center justify-center overflow-hidden rounded-md border bg-muted">
+                        <img
+                          src={imageSrc}
+                          alt={label || 'Artifact image'}
+                          className="max-h-48 w-full max-w-full object-contain"
+                        />
+                      </div>
+                    ) : artifact.content ? (
+                      <div className="min-h-[120px] overflow-hidden rounded-md border border-border bg-background">
+                        <iframe
+                          title={label || 'Artifact HTML output'}
+                          srcDoc={artifact.content}
+                          className="h-40 w-full"
+                          sandbox="allow-same-origin"
+                        />
+                      </div>
+                    ) : (
+                      <div className="flex min-h-[80px] items-center justify-center rounded-md border border-dashed border-muted-foreground/40 bg-muted/40 px-3 text-xs text-muted-foreground">
+                        No preview available.
+                      </div>
+                    )}
+                  </div>
+                  <div className="flex flex-wrap items-center justify-between gap-2 border-t border-border/60 bg-card px-3 py-2">
+                    <div className="flex min-w-0 items-center gap-2">
+                      <p className="truncate text-xs text-muted-foreground">
+                        Type: <span className="font-medium">{artifact.type}</span>
+                      </p>
+                      {artifact.updatedAt != null && (
+                        <span className="text-[11px] text-muted-foreground">
+                          · {formatTimeSinceLastUpdate(artifact.updatedAt)}
+                        </span>
+                      )}
+                    </div>
+                    <Button
+                      type="button"
+                      variant="outline"
+                      size="xs"
+                      className="h-7 px-2 text-xs"
+                      onClick={() => handleViewInFlux(artifact.nodeId)}
+                    >
+                      View in Flux
+                    </Button>
+                  </div>
+                </div>
+              )
+            })}
+          </div>
+        )}
+      </div>
+    </div>
+  )
+}
+

frontend/src/app/recollections/layout/RecollectionActionsContext.tsx

@@ -0,0 +1,259 @@
+/**
+ * Context for shared recollection actions: two slots (flux and logos) and layout-level import/export.
+ * Consumers use pathname to pick the active slot for title (save status, Save) and Edit/View menus (undo, redo, etc.).
+ */
+
+import React, { createContext, useCallback, useContext, useEffect, useRef, useState } from 'react'
+import { useLocation, useParams } from 'react-router-dom'
+import type { SaveStatus } from '@/app/canvas/useCanvasGraph'
+import {
+  getGraph,
+  setGraph,
+  getLogosContent,
+  setLogosContent,
+  upsertRenderOutputEntry,
+  RECOLLECTION_FILE_EXT,
+  RECOLLECTION_VERSION,
+  type StoredGraphState,
+  type StoredLogosContent,
+  type RenderOutputCacheEntry,
+} from '../state/recollectionStore'
+
+export type { RenderOutputCacheEntry }
+import type { AppNode, AppEdge } from '@/lib/graph/nodeTypes'
+import { backfillEdgeTargetTypes } from '@/app/canvas/canvasGraphUtils'
+import { toast } from 'sonner'
+
+export type { SaveStatus }
+
+/** Parsed recollection file format (import/export). */
+export type RecollectionFilePayload = {
+  version?: number
+  graph?: { nodes: unknown[]; edges: unknown[] }
+  logos?: StoredLogosContent
+}
+
+export type FluxSlot = {
+  saveStatus: SaveStatus
+  onSave: () => void
+  canSave: boolean
+  undo: () => void
+  redo: () => void
+  canUndo: boolean
+  canRedo: boolean
+  onRefreshFromStore: (graph: StoredGraphState) => void
+  onDuplicate?: () => void
+  onCopy?: () => void
+  onPaste?: () => void
+  canDuplicate?: boolean
+  canCopy?: boolean
+  onFitView?: () => void
+}
+
+export type LogosSlot = {
+  saveStatus: SaveStatus
+  onSave: () => void
+  canSave: boolean
+  undo: () => void
+  redo: () => void
+  canUndo: boolean
+  canRedo: boolean
+  onRefreshFromStore: () => void
+}
+
+export type RecollectionActionsContextValue = {
+  flux: FluxSlot | null
+  logos: LogosSlot | null
+  setFluxSlot: (slot: FluxSlot | null) => void
+  setLogosSlot: (slot: LogosSlot | null) => void
+  /** Whether the Flux view is active (pathname ends with /flux). */
+  isFluxActive: boolean
+  /** Whether the Logos view is active. */
+  isLogosActive: boolean
+  /** Active slot (flux or logos by pathname). */
+  activeSlot: FluxSlot | LogosSlot | null
+  onImport: () => void
+  onExport: () => void
+  /** Upsert a rendering node's output into the cache so Logos "Insert from Flux" block can show it. */
+  upsertRenderOutputToLogos: (entry: RenderOutputCacheEntry) => void
+}
+
+const RecollectionActionsContext = createContext<RecollectionActionsContextValue | null>(null)
+
+function validateAndWritePayload(
+  recollectionId: string,
+  payload: RecollectionFilePayload,
+  backfillEdges: (nodes: AppNode[], edges: AppEdge[]) => AppEdge[]
+): { graph?: StoredGraphState; logos?: StoredLogosContent } {
+  const result: { graph?: StoredGraphState; logos?: StoredLogosContent } = {}
+  if (payload.graph && Array.isArray(payload.graph.nodes) && Array.isArray(payload.graph.edges)) {
+    const nodes = payload.graph.nodes as AppNode[]
+    const edges = backfillEdges(nodes, payload.graph.edges as AppEdge[])
+    const graphState: StoredGraphState = {
+      version: payload.version ?? RECOLLECTION_VERSION,
+      nodes,
+      edges,
+    }
+    setGraph(recollectionId, graphState)
+    result.graph = graphState
+  }
+  if (payload.logos != null && Array.isArray(payload.logos)) {
+    if (payload.logos.every((item) => item != null && typeof item === 'object')) {
+      setLogosContent(recollectionId, payload.logos as StoredLogosContent)
+      result.logos = payload.logos as StoredLogosContent
+    }
+  }
+  return result
+}
+
+export function RecollectionActionsProvider({ children }: { children: React.ReactNode }) {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { pathname } = useLocation()
+  const [flux, setFluxSlotState] = useState<FluxSlot | null>(null)
+  const [logos, setLogosSlotState] = useState<LogosSlot | null>(null)
+  const importInputRef = useRef<HTMLInputElement>(null)
+  const fluxRef = useRef<FluxSlot | null>(null)
+  const logosRef = useRef<LogosSlot | null>(null)
+  const pathnameRef = useRef(pathname)
+  fluxRef.current = flux
+  logosRef.current = logos
+  pathnameRef.current = pathname
+
+  const isFluxActive = pathname.endsWith('/flux')
+  const isLogosActive = pathname.includes('/logos') || /\/recollections\/[^/]+\/?$/.test(pathname)
+  const activeSlot = isFluxActive ? flux : isLogosActive ? logos : null
+
+  const setFluxSlot = useCallback((slot: FluxSlot | null) => {
+    setFluxSlotState(() => slot)
+  }, [])
+  const setLogosSlot = useCallback((slot: LogosSlot | null) => {
+    setLogosSlotState(() => slot)
+  }, [])
+
+  useEffect(() => {
+    const onKeyDown = (ev: KeyboardEvent) => {
+      const mod = ev.ctrlKey || ev.metaKey
+      if (mod && ev.key.toLowerCase() === 's') {
+        const slot = activeSlot
+        if (slot?.onSave && slot?.canSave) {
+          ev.preventDefault()
+          ev.stopPropagation()
+          slot.onSave()
+        }
+      }
+    }
+    window.addEventListener('keydown', onKeyDown, true)
+    return () => window.removeEventListener('keydown', onKeyDown, true)
+  }, [activeSlot])
+
+  const onExport = useCallback(() => {
+    if (!recollectionId) return
+    const graph = getGraph(recollectionId)
+    const logosContent = getLogosContent(recollectionId)
+    const payload: RecollectionFilePayload = {
+      version: RECOLLECTION_VERSION,
+      ...(graph && { graph: { nodes: graph.nodes, edges: graph.edges } }),
+      ...(logosContent && { logos: logosContent }),
+    }
+    const blob = new Blob([JSON.stringify(payload, null, 2)], { type: 'application/json' })
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    a.download = `recollection${RECOLLECTION_FILE_EXT}`
+    a.click()
+    URL.revokeObjectURL(url)
+    toast.success('Recollection exported')
+  }, [recollectionId])
+
+  const onImport = useCallback(() => {
+    importInputRef.current?.click()
+  }, [])
+
+  const upsertRenderOutputToLogos = useCallback(
+    (entry: RenderOutputCacheEntry) => {
+      if (recollectionId) upsertRenderOutputEntry(recollectionId, entry)
+    },
+    [recollectionId]
+  )
+
+  const onImportFileChange = useCallback(
+    (e: React.ChangeEvent<HTMLInputElement>) => {
+      const file = e.target.files?.[0]
+      e.target.value = ''
+      if (!file || !recollectionId) return
+      const reader = new FileReader()
+      reader.onload = () => {
+        try {
+          const text = reader.result as string
+          const payload = JSON.parse(text) as RecollectionFilePayload
+          if (!payload || typeof payload !== 'object') {
+            toast.error('Invalid file: not valid JSON')
+            return
+          }
+          const written = validateAndWritePayload(recollectionId, payload, (nodes, edges) =>
+            backfillEdgeTargetTypes(nodes, edges)
+          )
+          const currentPath = pathnameRef.current
+          const fluxActive = currentPath.endsWith('/flux')
+          const logosActive = currentPath.includes('/logos') || /\/recollections\/[^/]+\/?$/.test(currentPath)
+          if (written.graph && fluxActive && fluxRef.current?.onRefreshFromStore) {
+            fluxRef.current.onRefreshFromStore(written.graph)
+          }
+          if ((written.graph != null || written.logos != null) && logosActive && logosRef.current?.onRefreshFromStore) {
+            logosRef.current.onRefreshFromStore()
+          }
+          if (payload.version != null && payload.version > RECOLLECTION_VERSION) {
+            toast.error('Recollection was created with a newer app version')
+          } else {
+            toast.success('Recollection loaded')
+          }
+        } catch {
+          toast.error('Invalid file: not valid JSON')
+        }
+      }
+      reader.readAsText(file)
+    },
+    [recollectionId]
+  )
+
+  const value: RecollectionActionsContextValue = React.useMemo(
+    () => ({
+      flux,
+      logos,
+      setFluxSlot,
+      setLogosSlot,
+      isFluxActive,
+      isLogosActive,
+      activeSlot,
+      onImport,
+      onExport,
+      upsertRenderOutputToLogos,
+    }),
+    [flux, logos, setFluxSlot, setLogosSlot, isFluxActive, isLogosActive, activeSlot, onImport, onExport, upsertRenderOutputToLogos]
+  )
+
+  return (
+    <RecollectionActionsContext.Provider value={value}>
+      {children}
+      <input
+        ref={importInputRef}
+        type="file"
+        accept=".json,application/json"
+        className="hidden"
+        aria-hidden
+        onChange={onImportFileChange}
+      />
+    </RecollectionActionsContext.Provider>
+  )
+}
+
+export function useRecollectionActions(): RecollectionActionsContextValue {
+  const ctx = useContext(RecollectionActionsContext)
+  if (!ctx) throw new Error('useRecollectionActions must be used within RecollectionActionsProvider')
+  return ctx
+}
+
+/** Returns the context value or null when outside RecollectionActionsProvider. Use when the consumer may render outside recollection layout. */
+export function useOptionalRecollectionActions(): RecollectionActionsContextValue | null {
+  return useContext(RecollectionActionsContext)
+}

frontend/src/app/recollections/layout/RecollectionEditViewMenus.tsx

@@ -0,0 +1,154 @@
+/**
+ * Shared Edit and View menus for recollections. Always rendered in the menubar;
+ * uses the active slot (flux or logos by pathname) for undo, redo, and Flux-only actions.
+ */
+
+import React, { useEffect, useMemo } from 'react'
+import {
+  Menubar,
+  MenubarContent,
+  MenubarItem,
+  MenubarMenu,
+  MenubarSeparator,
+  MenubarTrigger,
+} from '@/components/ui/menubar'
+import { Kbd, KbdGroup } from '@/components/ui/kbd'
+import { useRecollectionActions } from './RecollectionActionsContext'
+import { ClipboardPaste, Copy, CopyPlus, Redo2, Undo2 } from 'lucide-react'
+
+const UNDO_KEYS = { key: 'z', shiftKey: false }
+const REDO_KEYS = { key: 'z', shiftKey: true }
+
+function matchKey(ev: KeyboardEvent, want: { key: string; shiftKey: boolean }) {
+  const mod = ev.ctrlKey || ev.metaKey
+  return ev.key.toLowerCase() === want.key && !!mod && !!ev.shiftKey === want.shiftKey
+}
+
+export function RecollectionEditViewMenus() {
+  const { activeSlot, flux, isFluxActive } = useRecollectionActions()
+
+  const fluxSlot = isFluxActive ? flux : null
+
+  useEffect(() => {
+    if (!activeSlot) return
+    const onKeyDown = (ev: KeyboardEvent) => {
+      if (matchKey(ev, UNDO_KEYS) && activeSlot.canUndo) {
+        ev.preventDefault()
+        ev.stopPropagation()
+        activeSlot.undo()
+      } else if (matchKey(ev, REDO_KEYS) && activeSlot.canRedo) {
+        ev.preventDefault()
+        ev.stopPropagation()
+        activeSlot.redo()
+      }
+    }
+    window.addEventListener('keydown', onKeyDown, true)
+    return () => window.removeEventListener('keydown', onKeyDown, true)
+  }, [activeSlot])
+
+  const hasFluxOnly =
+    fluxSlot &&
+    (fluxSlot.onDuplicate != null || fluxSlot.onCopy != null || fluxSlot.onPaste != null)
+
+  const menus = useMemo(
+    () => (
+      <Menubar className="h-9 shrink-0 rounded-none border-0 bg-transparent p-0 shadow-none">
+        <MenubarMenu>
+          <MenubarTrigger className="h-9 font-normal text-muted-foreground">Edit</MenubarTrigger>
+          <MenubarContent>
+            <MenubarItem
+              onClick={() => activeSlot?.undo()}
+              disabled={!activeSlot?.canUndo}
+              className="gap-2"
+            >
+              <Undo2 className="h-4 w-4" />
+              Undo
+              <span className="ml-auto pl-4">
+                <KbdGroup>
+                  <Kbd>⌘ + Z</Kbd>
+                </KbdGroup>
+              </span>
+            </MenubarItem>
+            <MenubarItem
+              onClick={() => activeSlot?.redo()}
+              disabled={!activeSlot?.canRedo}
+              className="gap-2"
+            >
+              <Redo2 className="h-4 w-4" />
+              Redo
+              <span className="ml-auto pl-4">
+                <KbdGroup>
+                  <Kbd>⌘ + ⇧ + Z</Kbd>
+                </KbdGroup>
+              </span>
+            </MenubarItem>
+            {hasFluxOnly && fluxSlot && (
+              <>
+                <MenubarSeparator />
+                {fluxSlot.onDuplicate != null && (
+                  <MenubarItem
+                    onClick={fluxSlot.onDuplicate}
+                    disabled={!fluxSlot.canDuplicate}
+                    className="gap-2"
+                  >
+                    <CopyPlus className="h-4 w-4" />
+                    Duplicate
+                    <span className="ml-auto pl-4">
+                      <KbdGroup>
+                        <Kbd>⌘D</Kbd>
+                      </KbdGroup>
+                    </span>
+                  </MenubarItem>
+                )}
+                {fluxSlot.onCopy != null && (
+                  <MenubarItem
+                    onClick={fluxSlot.onCopy}
+                    disabled={!fluxSlot.canCopy}
+                    className="gap-2"
+                  >
+                    <Copy className="h-4 w-4" />
+                    Copy
+                    <span className="ml-auto pl-4">
+                      <KbdGroup>
+                        <Kbd>⌘C</Kbd>
+                      </KbdGroup>
+                    </span>
+                  </MenubarItem>
+                )}
+                {fluxSlot.onPaste != null && (
+                  <MenubarItem onClick={fluxSlot.onPaste} className="gap-2">
+                    <ClipboardPaste className="h-4 w-4" />
+                    Paste
+                    <span className="ml-auto pl-4">
+                      <KbdGroup>
+                        <Kbd>⌘V</Kbd>
+                      </KbdGroup>
+                    </span>
+                  </MenubarItem>
+                )}
+              </>
+            )}
+          </MenubarContent>
+        </MenubarMenu>
+        <MenubarMenu>
+          <MenubarTrigger className="h-9 font-normal text-muted-foreground">View</MenubarTrigger>
+          <MenubarContent>
+            {fluxSlot?.onFitView && (
+              <MenubarItem onClick={fluxSlot.onFitView} className="gap-2">
+                Fit View
+                <span className="ml-auto pl-4">
+                  <KbdGroup>
+                    <Kbd>⌘0</Kbd>
+                  </KbdGroup>
+                </span>
+              </MenubarItem>
+            )}
+          </MenubarContent>
+        </MenubarMenu>
+      </Menubar>
+    ),
+    [activeSlot, fluxSlot, hasFluxOnly]
+  )
+
+  return menus
+}

frontend/src/app/recollections/layout/RecollectionFileMenu.tsx

@@ -0,0 +1,102 @@
+/**
+ * File menu for a recollection (emanation).
+ * Hosts Save, Rename, Import, Export that used to live under the title dropdown.
+ */
+
+import React, { useMemo, useState } from 'react'
+import {
+  DropdownMenu,
+  DropdownMenuContent,
+  DropdownMenuItem,
+  DropdownMenuPortal,
+  DropdownMenuSeparator,
+  DropdownMenuTrigger,
+} from '@/components/ui/dropdown-menu'
+import { Kbd, KbdGroup } from '@/components/ui/kbd'
+import { useRecollectionActions } from './RecollectionActionsContext'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import { RenameRecollectionDialog } from './RenameRecollectionDialog'
+import { Download, FolderOpen, Pencil, Save } from 'lucide-react'
+import { useParams } from 'react-router-dom'
+
+export function RecollectionFileMenu() {
+  const { activeSlot, onImport, onExport } = useRecollectionActions()
+  const { recollections, renameRecollection } = usePlatform()
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+
+  const [renameModalOpen, setRenameModalOpen] = useState(false)
+
+  const onSave = activeSlot?.onSave
+  const canSave = activeSlot?.canSave ?? false
+
+  const recollectionName = useMemo(
+    () => (recollectionId ? recollections.find((p) => p.id === recollectionId)?.name ?? '' : ''),
+    [recollectionId, recollections]
+  )
+
+  const menuItems = useMemo(
+    () => (
+      <>
+        {recollectionId && onSave != null && (
+          <>
+            <DropdownMenuItem onClick={onSave} disabled={!canSave} className="gap-2">
+              <Save className="h-4 w-4" />
+              Save
+              <span className="ml-auto pl-4">
+                <KbdGroup>
+                  <Kbd>⌘S</Kbd>
+                </KbdGroup>
+              </span>
+            </DropdownMenuItem>
+            <DropdownMenuSeparator />
+          </>
+        )}
+        {recollectionId && (
+          <>
+            <DropdownMenuItem onClick={() => setRenameModalOpen(true)} className="gap-2">
+              <Pencil className="h-4 w-4" />
+              Rename
+            </DropdownMenuItem>
+            <DropdownMenuSeparator />
+          </>
+        )}
+        <DropdownMenuItem onClick={onImport} className="gap-2">
+          <FolderOpen className="h-4 w-4" />
+          Import…
+        </DropdownMenuItem>
+        <DropdownMenuItem onClick={onExport} className="gap-2">
+          <Download className="h-4 w-4" />
+          Export…
+        </DropdownMenuItem>
+      </>
+    ),
+    [recollectionId, onSave, canSave, onImport, onExport]
+  )
+
+  return (
+    <>
+      <DropdownMenu>
+        <DropdownMenuTrigger className="flex h-9 shrink-0 items-center rounded-sm px-2 py-0 text-sm font-normal text-muted-foreground outline-none focus:bg-accent focus:text-accent-foreground hover:bg-accent hover:text-accent-foreground data-[state=open]:bg-accent">
+          File
+        </DropdownMenuTrigger>
+        <DropdownMenuPortal>
+          <DropdownMenuContent align="start" className="z-[200] min-w-[12rem]">
+            {menuItems}
+          </DropdownMenuContent>
+        </DropdownMenuPortal>
+      </DropdownMenu>
+      <RenameRecollectionDialog
+        open={renameModalOpen}
+        onOpenChange={setRenameModalOpen}
+        recollectionId={recollectionId ?? ''}
+        initialName={recollectionName}
+        recollections={recollections}
+        onRename={(id, newName) => {
+          renameRecollection(id, newName)
+          setRenameModalOpen(false)
+        }}
+      />
+    </>
+  )
+}
+

frontend/src/app/recollections/layout/RecollectionMenubar.tsx

@@ -0,0 +1,114 @@
+/**
+ * Recollection menubar: Back | breadcrumbs (left) | view switcher + File + Edit + save status (center).
+ */
+
+import React from 'react'
+import { Link, useLocation, useParams } from 'react-router-dom'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import {
+  Breadcrumb,
+  BreadcrumbItem,
+  BreadcrumbLink,
+  BreadcrumbList,
+  BreadcrumbPage,
+  BreadcrumbSeparator,
+} from '@/components/ui/breadcrumb'
+import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
+import { CheckCircle2, CircleDot, Loader2 } from 'lucide-react'
+import { RecollectionEditViewMenus } from './RecollectionEditViewMenus'
+import { RecollectionViewSwitcher } from './RecollectionViewSwitcher'
+import { RecollectionFileMenu } from './RecollectionFileMenu'
+import { useRecollectionActions } from './RecollectionActionsContext'
+import { getMode, viewLabel } from './recollectionNav'
+
+export function RecollectionMenubar() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { pathname } = useLocation()
+  const { recollections } = usePlatform()
+  const { activeSlot } = useRecollectionActions()
+  const saveStatus = activeSlot?.saveStatus ?? null
+
+  const recollection = recollectionId ? recollections.find((p) => p.id === recollectionId) : null
+  const mode = getMode(pathname)
+  const base = recollectionId ? `/recollections/${recollectionId}` : ''
+
+  return (
+    <div className="relative flex h-9 w-full shrink-0 items-center gap-2 overflow-visible border-b border-border/40 bg-background px-2">
+      <div className="flex items-center gap-2">
+        {base && (
+          <Breadcrumb>
+            <BreadcrumbList className="text-xs">
+              <BreadcrumbItem>
+                <BreadcrumbLink asChild>
+                  <Link
+                    to="/recollections"
+                    aria-label="Back to recollections"
+                    className="flex shrink-0 items-center rounded-sm px-2 py-1 text-sm outline-none focus:bg-accent focus:text-accent-foreground hover:bg-accent hover:text-accent-foreground"
+                  >
+                    <span
+                      className="size-4 shrink-0 rounded-[2px] opacity-90"
+                      style={{
+                        maskImage: 'url(/app-icon.svg)',
+                        maskRepeat: 'no-repeat',
+                        maskPosition: 'center',
+                        maskSize: 'contain',
+                        WebkitMaskImage: 'url(/app-icon.svg)',
+                        WebkitMaskRepeat: 'no-repeat',
+                        WebkitMaskPosition: 'center',
+                        WebkitMaskSize: 'contain',
+                        backgroundColor: 'currentColor',
+                      }}
+                      aria-hidden
+                    />
+                  </Link>
+                </BreadcrumbLink>
+              </BreadcrumbItem>
+              <BreadcrumbSeparator />
+              <BreadcrumbItem>
+                <BreadcrumbLink asChild>
+                  <Link to={base}>{recollection?.name ?? 'Recollection'}</Link>
+                </BreadcrumbLink>
+              </BreadcrumbItem>
+              <BreadcrumbSeparator />
+              <BreadcrumbItem>
+                <BreadcrumbPage>{viewLabel(mode)}</BreadcrumbPage>
+              </BreadcrumbItem>
+            </BreadcrumbList>
+          </Breadcrumb>
+        )}
+      </div>
+      <div className="pointer-events-none absolute left-1/2 top-1/2 flex min-w-0 -translate-x-1/2 -translate-y-1/2 items-center justify-center">
+        <div className="pointer-events-auto flex min-w-0 items-center gap-2">
+          <RecollectionViewSwitcher />
+          <RecollectionFileMenu />
+          <RecollectionEditViewMenus />
+          {/* Fixed-width slot so layout does not jump when saveStatus is null (e.g. on Katalogos) */}
+          <span
+            className="flex h-9 w-9 shrink-0 items-center justify-center text-muted-foreground"
+            aria-live="polite"
+            aria-label={
+              saveStatus === 'saving' ? 'Saving' : saveStatus === 'unsaved' ? 'Unsaved changes' : saveStatus === 'saved' ? 'All changes saved' : undefined
+            }
+          >
+            {saveStatus != null && (
+              <TooltipProvider delayDuration={300}>
+                <Tooltip>
+                  <TooltipTrigger asChild>
+                    <span className="flex size-5 items-center justify-center">
+                      {saveStatus === 'saving' && <Loader2 className="size-3.5 animate-spin" aria-hidden />}
+                      {saveStatus === 'unsaved' && <CircleDot className="size-3.5" aria-hidden />}
+                      {saveStatus === 'saved' && <CheckCircle2 className="size-3.5 text-muted-foreground/70" aria-hidden />}
+                    </span>
+                  </TooltipTrigger>
+                  <TooltipContent side="bottom">
+                    {saveStatus === 'saving' ? 'Saving…' : saveStatus === 'unsaved' ? 'Unsaved changes' : 'All changes saved'}
+                  </TooltipContent>
+                </Tooltip>
+              </TooltipProvider>
+            )}
+          </span>
+        </div>
+      </div>
+    </div>
+  )
+}

frontend/src/app/recollections/layout/RecollectionSidebar.tsx

@@ -0,0 +1,111 @@
+/**
+ * Recollection sidebar: Logos (pages), Katalogos, Flux. Shared by all recollection routes.
+ */
+
+import React, { useCallback } from 'react'
+import { useParams, useLocation, useNavigate } from 'react-router-dom'
+import { Button } from '@/components/ui/button'
+import { Plus, FileText } from 'lucide-react'
+import { FluxIcon } from '@/lib/icons'
+import { cn } from '@/lib/utils'
+import { useRecollectionSidebar } from './RecollectionSidebarContext'
+import { TreeBrowser } from './TreeBrowser'
+import {
+  SidebarContent,
+  SidebarGroup,
+  SidebarGroupContent,
+  SidebarGroupLabel,
+  SidebarMenu,
+  SidebarMenuItem,
+  sidebarMenuButtonVariants,
+} from '@/components/ui/sidebar'
+
+export function RecollectionSidebar() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { pathname } = useLocation()
+  const navigate = useNavigate()
+  const { tree, handleSelectPage, handleTreeChange } = useRecollectionSidebar()
+
+  const base = recollectionId ? `/recollections/${recollectionId}` : ''
+  const baseLogos = `${base}/logos`
+  const isKatalogosView = pathname.endsWith('/logos/katalogos')
+  const isFluxView = pathname.endsWith('/flux')
+
+  const handleAddPage = useCallback(() => {
+    // Add a new top-level page
+    const maxPos = Math.max(0, ...tree.filter((p) => p.parentId === null).map((p) => p.position), -1)
+    const newPage = {
+      id: `page-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`,
+      title: 'Untitled',
+      parentId: null,
+      position: maxPos + 1,
+    }
+    handleTreeChange([...tree, newPage])
+    handleSelectPage(newPage.id)
+    navigate(`${baseLogos}?page=${encodeURIComponent(newPage.id)}`)
+  }, [tree, handleTreeChange, handleSelectPage, baseLogos, navigate])
+
+  return (
+    <div
+      className="flex h-full w-[var(--sidebar-width)] shrink-0 flex-col border-r border-sidebar-border bg-sidebar text-sidebar-foreground"
+      style={{ '--sidebar-width': '16rem' } as React.CSSProperties}
+    >
+      <SidebarContent className="flex-1 overflow-y-auto border-0 bg-transparent">
+        <SidebarGroup>
+          <div className="flex items-center justify-between gap-2 py-1.5">
+            <SidebarGroupLabel className="py-0">Logos</SidebarGroupLabel>
+            <Button
+              type="button"
+              variant="ghost"
+              size="sm"
+              className="h-6 gap-1 px-1.5 text-xs text-sidebar-foreground hover:bg-sidebar-accent hover:text-sidebar-accent-foreground"
+              onClick={handleAddPage}
+            >
+              <Plus className="size-3.5" />
+              New page
+            </Button>
+          </div>
+          <SidebarGroupContent>
+            <TreeBrowser />
+          </SidebarGroupContent>
+        </SidebarGroup>
+        <SidebarGroup>
+          <SidebarGroupLabel>Katalogos</SidebarGroupLabel>
+          <SidebarGroupContent>
+            <SidebarMenu>
+              <SidebarMenuItem>
+                <button
+                  type="button"
+                  data-active={isKatalogosView}
+                  className={cn(sidebarMenuButtonVariants({ size: 'default' }), 'w-full')}
+                  onClick={() => navigate(`${base}/logos/katalogos`)}
+                >
+                  <FileText className="size-4 shrink-0 text-sidebar-foreground/70" />
+                  <span className="truncate">Artifacts</span>
+                </button>
+              </SidebarMenuItem>
+            </SidebarMenu>
+          </SidebarGroupContent>
+        </SidebarGroup>
+        <SidebarGroup>
+          <SidebarGroupLabel>Flux</SidebarGroupLabel>
+          <SidebarGroupContent>
+            <SidebarMenu>
+              <SidebarMenuItem>
+                <button
+                  type="button"
+                  data-active={isFluxView}
+                  className={cn(sidebarMenuButtonVariants({ size: 'default' }), 'w-full')}
+                  onClick={() => navigate(`${base}/flux`)}
+                >
+                  <FluxIcon className="size-4 shrink-0 text-sidebar-foreground/70" />
+                  <span className="truncate">Canvas</span>
+                </button>
+              </SidebarMenuItem>
+            </SidebarMenu>
+          </SidebarGroupContent>
+        </SidebarGroup>
+      </SidebarContent>
+    </div>
+  )
+}

frontend/src/app/recollections/layout/RecollectionSidebarContext.tsx

@@ -0,0 +1,114 @@
+/**
+ * Context for the recollection sidebar: Logos page tree and active page, shared by
+ * RecollectionSidebar and LogosPage. Load/persist and URL sync live here.
+ */
+
+import React, { createContext, useCallback, useContext, useEffect, useState } from 'react'
+import { useParams, useSearchParams } from 'react-router-dom'
+import {
+  getLogosContent,
+  getLogosPageTree,
+  setLogosPageTree,
+  setLogosContentForPage,
+  removeLogosPageContent,
+  type LogosPageMeta,
+  type LogosPageId,
+} from '../state/recollectionStore'
+
+const MAIN_PAGE_ID: LogosPageId = 'main'
+
+export type RecollectionSidebarContextValue = {
+  tree: LogosPageMeta[]
+  activePageId: LogosPageId | null
+  setTree: React.Dispatch<React.SetStateAction<LogosPageMeta[]>>
+  handleSelectPage: (id: LogosPageId) => void
+  handleTreeChange: (tree: LogosPageMeta[]) => void
+  handleDeletePage: (pageId: LogosPageId) => void
+}
+
+const RecollectionSidebarContext = createContext<RecollectionSidebarContextValue | null>(null)
+
+export function useRecollectionSidebar(): RecollectionSidebarContextValue {
+  const ctx = useContext(RecollectionSidebarContext)
+  if (!ctx) throw new Error('useRecollectionSidebar must be used within RecollectionSidebarProvider')
+  return ctx
+}
+
+export function RecollectionSidebarProvider({ children }: { children: React.ReactNode }) {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const [searchParams, setSearchParams] = useSearchParams()
+  const [tree, setTree] = useState<LogosPageMeta[]>([])
+  const [activePageId, setActivePageId] = useState<LogosPageId | null>(null)
+
+  const baseLogosPath = recollectionId ? `/recollections/${recollectionId}/logos` : ''
+
+  const handleSelectPage = useCallback(
+    (id: LogosPageId) => {
+      setActivePageId(id)
+      if (recollectionId) {
+        setSearchParams({ page: id }, { replace: true })
+      }
+    },
+    [recollectionId, setSearchParams]
+  )
+
+  const handleTreeChange = useCallback((newTree: LogosPageMeta[]) => {
+    setTree(newTree)
+  }, [])
+
+  const handleDeletePage = useCallback(
+    (pageId: LogosPageId) => {
+      if (recollectionId) removeLogosPageContent(recollectionId, pageId)
+    },
+    [recollectionId]
+  )
+
+  // Load page tree from storage only when recollection changes (not on every searchParams change).
+  // Otherwise adding a new page would trigger searchParams change and this would overwrite tree before persist.
+  useEffect(() => {
+    if (!recollectionId) return
+    let t = getLogosPageTree(recollectionId)
+    if (t.length === 0) {
+      const legacy = getLogosContent(recollectionId)
+      const main: LogosPageMeta = { id: MAIN_PAGE_ID, title: 'Main', parentId: null, position: 0 }
+      setLogosContentForPage(recollectionId, MAIN_PAGE_ID, legacy ?? [])
+      setLogosPageTree(recollectionId, [main])
+      t = [main]
+    }
+    setTree(t)
+  }, [recollectionId])
+
+  // Sync activePageId from URL when searchParams or tree changes (e.g. after adding a page).
+  useEffect(() => {
+    if (!recollectionId) return
+    const pageFromUrl = searchParams.get('page')
+    setActivePageId((prev) => {
+      const validIdFromUrl = pageFromUrl && tree.some((p) => p.id === pageFromUrl) ? pageFromUrl : null
+      if (validIdFromUrl) return validIdFromUrl
+      const firstId = tree[0]?.id ?? null
+      if (prev != null && tree.some((p) => p.id === prev)) return prev
+      return firstId
+    })
+  }, [recollectionId, searchParams, tree])
+
+  // Persist tree when sidebar changes it.
+  useEffect(() => {
+    if (!recollectionId || tree.length === 0) return
+    setLogosPageTree(recollectionId, tree)
+  }, [recollectionId, tree])
+
+  const value: RecollectionSidebarContextValue = {
+    tree,
+    activePageId,
+    setTree,
+    handleSelectPage,
+    handleTreeChange,
+    handleDeletePage,
+  }
+
+  return (
+    <RecollectionSidebarContext.Provider value={value}>
+      {children}
+    </RecollectionSidebarContext.Provider>
+  )
+}

frontend/src/app/recollections/layout/RecollectionViewSwitcher.tsx

@@ -0,0 +1,94 @@
+/**
+ * View switcher: circle with current view icon; click cycles Logos → Katalogos → Flux.
+ * Keyboard shortcut: ⌘⇧↑ / ⌘⇧↓ to cycle view.
+ */
+
+import React, { useCallback, useEffect, useMemo } from 'react'
+import { useLocation, useNavigate, useParams } from 'react-router-dom'
+import { FluxIcon } from '@/lib/icons'
+import { FileText, LayoutGrid } from 'lucide-react'
+import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
+import { getMode, pathForMode, RECOLLECTION_VIEW_MODES, viewLabel } from './recollectionNav'
+
+const ICON_SLOT_SIZE_REM = 2 // size-8 = 2rem
+
+function shortcutLabel() {
+  const isMac = typeof navigator !== 'undefined' && /Mac|iPod|iPhone|iPad/.test(navigator.platform)
+  return isMac ? '⌘⇧↑ / ⌘⇧↓' : 'Ctrl+Shift+↑ / Ctrl+Shift+↓'
+}
+
+export function RecollectionViewSwitcher() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { pathname } = useLocation()
+  const navigate = useNavigate()
+  const base = recollectionId ? `/recollections/${recollectionId}` : ''
+
+  const mode = useMemo(() => getMode(pathname), [pathname])
+  const modeIndex = RECOLLECTION_VIEW_MODES.indexOf(mode)
+
+  const goRelative = useCallback(
+    (delta: 1 | -1) => {
+      if (!base) return
+      const nextIndex = (modeIndex + delta + RECOLLECTION_VIEW_MODES.length) % RECOLLECTION_VIEW_MODES.length
+      navigate(pathForMode(base, RECOLLECTION_VIEW_MODES[nextIndex]))
+    },
+    [base, modeIndex, navigate]
+  )
+
+  const cycle = useCallback(() => {
+    goRelative(1)
+  }, [goRelative])
+
+  useEffect(() => {
+    const onKeyDown = (ev: KeyboardEvent) => {
+      const isMod = ev.ctrlKey || ev.metaKey
+      const isShortcut = isMod && ev.shiftKey && (ev.key === 'ArrowDown' || ev.key === 'ArrowUp')
+      if (!isShortcut) return
+      ev.preventDefault()
+      if (ev.key === 'ArrowDown') goRelative(1)
+      else if (ev.key === 'ArrowUp') goRelative(-1)
+    }
+    window.addEventListener('keydown', onKeyDown, true)
+    return () => window.removeEventListener('keydown', onKeyDown, true)
+  }, [goRelative])
+
+  if (!base) return null
+
+  const tooltipText = `${viewLabel(mode)} (${shortcutLabel()})`
+  const translateY = -modeIndex * ICON_SLOT_SIZE_REM
+
+  return (
+    <div className="flex h-9 shrink-0 items-center">
+      <TooltipProvider delayDuration={300}>
+        <Tooltip>
+          <TooltipTrigger asChild>
+            <button
+              type="button"
+              onClick={cycle}
+              aria-label={tooltipText}
+              className="flex size-8 shrink-0 items-start justify-center overflow-hidden rounded-full transition-colors hover:bg-accent hover:text-accent-foreground focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-2 focus:ring-offset-background"
+            >
+              <div
+                className="flex flex-col transition-transform duration-200 ease-out"
+                style={{ transform: `translateY(${translateY}rem)` }}
+              >
+                <div className="flex size-8 flex-shrink-0 items-center justify-center [&_svg]:shrink-0">
+                  <FileText className="size-3.5 text-muted-foreground" />
+                </div>
+                <div className="flex size-8 flex-shrink-0 items-center justify-center [&_svg]:shrink-0">
+                  <LayoutGrid className="size-3.5 text-muted-foreground" />
+                </div>
+                <div className="flex size-8 flex-shrink-0 items-center justify-center [&_svg]:shrink-0">
+                  <span className="inline-flex size-3.5 shrink-0 items-center justify-center">
+                    <FluxIcon className="size-full text-muted-foreground" />
+                  </span>
+                </div>
+              </div>
+            </button>
+          </TooltipTrigger>
+          <TooltipContent side="bottom">{tooltipText}</TooltipContent>
+        </Tooltip>
+      </TooltipProvider>
+    </div>
+  )
+}

frontend/src/app/recollections/layout/RecollectionsPageBackground.tsx

@@ -0,0 +1,99 @@
+/**
+ * Subtle animated dot grid background for RecollectionsPage.
+ * Matches canvas grid (20px gap), with gentle wave movement.
+ */
+
+import React, { useCallback, useEffect, useRef } from 'react'
+
+const GAP = 20
+const SPEED = 0.010
+const AMPLITUDE = 4
+const DOT_SIZE = 1.2
+const PULSE_AMOUNT = 0.25
+
+function getDotColor(): string {
+  if (typeof document === 'undefined') return 'rgba(128,128,128,0.25)'
+  const isDark = document.documentElement.classList.contains('dark')
+  return isDark ? 'rgba(255,255,255,0.18)' : 'rgba(0,0,0,0.12)'
+}
+
+export function RecollectionsPageBackground({ className }: { className?: string }) {
+  const canvasRef = useRef<HTMLCanvasElement>(null)
+  const timeRef = useRef(0)
+  const rafRef = useRef<number>(0)
+
+  const draw = useCallback(() => {
+    const canvas = canvasRef.current
+    if (!canvas) return
+
+    const ctx = canvas.getContext('2d')
+    if (!ctx) return
+
+    const { width, height } = canvas
+    const cols = Math.floor(width / GAP) + 2
+    const rows = Math.floor(height / GAP) + 2
+    const t = timeRef.current
+
+    ctx.fillStyle = 'transparent'
+    ctx.clearRect(0, 0, width, height)
+
+    const dotColor = getDotColor()
+
+    for (let row = 0; row < rows; row++) {
+      for (let col = 0; col < cols; col++) {
+        const baseX = col * GAP
+        const baseY = row * GAP
+
+        const w1 = Math.sin(t * SPEED + baseX * 0.008 + baseY * 0.006) * AMPLITUDE
+        const w2 = Math.sin(t * SPEED * 0.7 - baseX * 0.012 + baseY * 0.01) * AMPLITUDE * 0.5
+        const w3 = Math.sin(t * SPEED * 1.2 + baseY * 0.015) * AMPLITUDE * 0.3
+
+        const x = baseX + w1 + w2 + w3
+        const y = baseY + w1 * 0.6 + w3 * 0.4
+
+        const size = DOT_SIZE + Math.sin(t * SPEED * 2 + baseX * 0.02) * PULSE_AMOUNT
+
+        ctx.beginPath()
+        ctx.arc(x, y, size, 0, Math.PI * 2)
+        ctx.fillStyle = dotColor
+        ctx.fill()
+      }
+    }
+
+    timeRef.current += 1
+    rafRef.current = requestAnimationFrame(draw)
+  }, [])
+
+  useEffect(() => {
+    const canvas = canvasRef.current
+    if (!canvas) return
+
+    const resize = () => {
+      const dpr = Math.min(window.devicePixelRatio ?? 1, 2)
+      const rect = canvas.getBoundingClientRect()
+      canvas.width = Math.round(rect.width * dpr)
+      canvas.height = Math.round(rect.height * dpr)
+      canvas.style.width = `${rect.width}px`
+      canvas.style.height = `${rect.height}px`
+      const ctx = canvas.getContext('2d')
+      if (ctx) ctx.setTransform(dpr, 0, 0, dpr, 0, 0)
+    }
+
+    resize()
+    window.addEventListener('resize', resize)
+    rafRef.current = requestAnimationFrame(draw)
+    return () => {
+      window.removeEventListener('resize', resize)
+      if (rafRef.current) cancelAnimationFrame(rafRef.current)
+    }
+  }, [draw])
+
+  return (
+    <canvas
+      ref={canvasRef}
+      className={className}
+      aria-hidden
+      style={{ display: 'block', width: '100%', height: '100%' }}
+    />
+  )
+}

frontend/src/app/recollections/layout/RenameRecollectionDialog.tsx

@@ -0,0 +1,94 @@
+/**
+ * Shared modal for renaming a recollection. Used by RecollectionsPage and RecollectionFileMenu.
+ */
+
+import React, { useCallback, useEffect, useRef, useState } from 'react'
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from '@/components/ui/dialog'
+import { Button } from '@/components/ui/button'
+import { Input } from '@/components/ui/input'
+
+export type RenameRecollectionDialogProps = {
+  open: boolean
+  onOpenChange: (open: boolean) => void
+  recollectionId: string
+  initialName: string
+  recollections: { id: string; name: string }[]
+  onRename: (id: string, newName: string) => void
+}
+
+export function RenameRecollectionDialog({
+  open,
+  onOpenChange,
+  recollectionId,
+  initialName,
+  recollections,
+  onRename,
+}: RenameRecollectionDialogProps) {
+  const [value, setValue] = useState(initialName)
+  const inputRef = useRef<HTMLInputElement>(null)
+
+  useEffect(() => {
+    if (open) {
+      setValue(initialName)
+      const t = setTimeout(() => inputRef.current?.focus(), 0)
+      return () => clearTimeout(t)
+    }
+  }, [open, initialName])
+
+  const handleClose = useCallback(() => onOpenChange(false), [onOpenChange])
+
+  const handleSubmit = useCallback(() => {
+    const trimmed = value.trim()
+    if (!trimmed) return
+    onRename(recollectionId, trimmed)
+    onOpenChange(false)
+  }, [recollectionId, value, onRename, onOpenChange])
+
+  const isDuplicateName =
+    !!value.trim() &&
+    recollections.some(
+      (p) => p.id !== recollectionId && p.name.toLowerCase() === value.trim().toLowerCase()
+    )
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent onCloseAutoFocus={(e) => e.preventDefault()}>
+        <DialogHeader>
+          <DialogTitle>Rename recollection</DialogTitle>
+          <DialogDescription>Enter a new name for this recollection.</DialogDescription>
+        </DialogHeader>
+        <Input
+          ref={inputRef}
+          value={value}
+          onChange={(e) => setValue(e.target.value)}
+          onKeyDown={(e) => {
+            if (e.key === 'Enter') handleSubmit()
+            if (e.key === 'Escape') handleClose()
+          }}
+          placeholder="Recollection name"
+          aria-label="Recollection name"
+        />
+        {isDuplicateName && (
+          <p className="text-xs text-amber-600 dark:text-amber-500">
+            A recollection with this name already exists.
+          </p>
+        )}
+        <DialogFooter>
+          <Button variant="outline" onClick={handleClose}>
+            Cancel
+          </Button>
+          <Button onClick={handleSubmit} disabled={!value.trim()}>
+            Save
+          </Button>
+        </DialogFooter>
+      </DialogContent>
+    </Dialog>
+  )
+}

frontend/src/app/recollections/layout/TreeBrowser.tsx

@@ -0,0 +1,609 @@
+/**
+ * TreeBrowser: A tree browser component using react-arborist for managing
+ * Logos pages in a hierarchical folder structure.
+ * 
+ * Features:
+ * - Drag and drop reordering
+ * - Folder expansion/collapse
+ * - Context menu for actions
+ * - Shadcn theme integration
+ * - Inline editing for page titles
+ * - Smooth animations
+ * - Search functionality
+ * - Expand/collapse all
+ */
+
+import React, { useCallback, useMemo, useRef, useState } from 'react'
+import { useResizeHeight } from '@/hooks/useResizeHeight'
+import {
+  Tree,
+  NodeApi,
+  NodeRendererProps,
+  RowRendererProps,
+  TreeApi,
+  type CursorProps,
+} from 'react-arborist'
+import { cn } from '@/lib/utils'
+import {
+  FileText,
+  ChevronRight,
+  ChevronDown,
+  Plus,
+  MoreHorizontal,
+  Trash2,
+  Pencil,
+  Search,
+  ChevronsDownUp,
+  ChevronsUpDown,
+  X,
+  GripVertical,
+} from 'lucide-react'
+import { Button } from '@/components/ui/button'
+import {
+  DropdownMenu,
+  DropdownMenuContent,
+  DropdownMenuItem,
+  DropdownMenuSeparator,
+  DropdownMenuTrigger,
+} from '@/components/ui/dropdown-menu'
+import { Input } from '@/components/ui/input'
+import { useRecollectionSidebar } from './RecollectionSidebarContext'
+import { useParams, useNavigate, useLocation } from 'react-router-dom'
+import type { LogosPageMeta } from '../state/recollectionStore'
+import { removeLogosPageContent } from '../state/recollectionStore'
+
+// Tree node: page metadata plus tree shape (react-arborist `node.data` is this whole object).
+type TreeNode = LogosPageMeta & {
+  children?: TreeNode[]
+  isFolder: boolean
+}
+
+// Convert flat tree to hierarchical structure
+function buildTree(pages: LogosPageMeta[]): TreeNode[] {
+  const pageMap = new Map<string, TreeNode>()
+  const rootNodes: TreeNode[] = []
+
+  // First pass: create all nodes
+  pages.forEach((page) => {
+    pageMap.set(page.id, {
+      ...page,
+      children: [],
+      isFolder: false,
+    })
+  })
+
+  // Second pass: build parent-child relationships
+  pages.forEach((page) => {
+    const node = pageMap.get(page.id)!
+    if (page.parentId === null) {
+      rootNodes.push(node)
+    } else {
+      const parent = pageMap.get(page.parentId)
+      if (parent) {
+        parent.children?.push(node)
+        parent.isFolder = true
+      }
+    }
+  })
+
+  // Sort children by position
+  function sortNodes(nodes: TreeNode[]) {
+    nodes.sort((a, b) => a.position - b.position)
+    nodes.forEach((node) => sortNodes(node.children || []))
+  }
+  sortNodes(rootNodes)
+
+  return rootNodes
+}
+
+// Memoize the buildTree result to avoid unnecessary re-creation
+function useTreeNodes(tree: LogosPageMeta[]) {
+  return useMemo(() => buildTree(tree), [tree])
+}
+
+// Inline editable title component
+function EditableTitle({
+  title,
+  onSave,
+  onCancel,
+}: {
+  title: string
+  onSave: (newTitle: string) => void
+  onCancel: () => void
+}) {
+  const inputRef = useRef<HTMLInputElement>(null)
+
+  React.useEffect(() => {
+    inputRef.current?.focus()
+    inputRef.current?.select()
+  }, [])
+
+  const handleKeyDown = (e: React.KeyboardEvent) => {
+    if (e.key === 'Enter') {
+      onSave(inputRef.current?.value || '')
+    } else if (e.key === 'Escape') {
+      onCancel()
+    }
+  }
+
+  return (
+    <input
+      ref={inputRef}
+      type="text"
+      defaultValue={title}
+      onBlur={(e) => onSave(e.currentTarget.value)}
+      onKeyDown={handleKeyDown}
+      className="w-full rounded px-1 py-0.5 text-sm outline-none ring-2 ring-ring focus:ring-2 transition-all duration-200 bg-background"
+      onClick={(e) => e.stopPropagation()}
+    />
+  )
+}
+
+const ROW_INDENT_PX = 20
+const ROW_GUTTER_PX = 8
+
+/**
+ * Line cursor = “insert as sibling at this indent” (not “drop into folder”).
+ * Triangle + dashed rail read as a slot between rows; matches sidebar theme.
+ */
+const LogosDropCursor = React.memo(function LogosDropCursor({ top, left, indent }: CursorProps) {
+  return (
+    <div
+      role="presentation"
+      aria-hidden
+      className="pointer-events-none absolute z-20 flex items-center gap-1.5"
+      style={{
+        top: top - 5,
+        left: left + ROW_GUTTER_PX,
+        right: Math.max(indent, ROW_GUTTER_PX),
+      }}
+    >
+      <span className="flex h-3 w-2.5 shrink-0 items-center justify-center text-primary drop-shadow-sm">
+        <svg width="9" height="10" viewBox="0 0 9 10" fill="currentColor" aria-hidden>
+          <path d="M0 5 L9 1.5 L9 8.5 Z" />
+        </svg>
+      </span>
+      <div className="flex h-3 min-w-[2rem] flex-1 items-center">
+        <div
+          className={cn(
+            'h-0 w-full border-t-2 border-dashed border-primary',
+            'shadow-[0_1px_0_0_hsl(var(--primary)/0.35)]',
+            'motion-safe:animate-[tree-drop-line-pulse_1.8s_ease-in-out_infinite]'
+          )}
+        />
+      </div>
+    </div>
+  )
+})
+
+/**
+ * Drag ref on a compact handle at the start of the row; handle is a floating pill shown on row hover
+ * (always visible on coarse pointers). Title/icon strip is click-to-navigate only.
+ */
+function LogosTreeNode({ node, dragHandle, style }: NodeRendererProps<TreeNode>) {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const navigate = useNavigate()
+  const { tree, handleSelectPage, handleTreeChange } = useRecollectionSidebar()
+
+  const base = recollectionId ? `/recollections/${recollectionId}` : ''
+  const baseLogos = `${base}/logos`
+
+  const handleToggle = useCallback(
+    (e: React.MouseEvent) => {
+      e.stopPropagation()
+      node.toggle()
+    },
+    [node]
+  )
+
+  const handleSelect = useCallback(
+    (e: React.MouseEvent) => {
+      if (!node.state.isEditing && !node.state.isDragging) {
+        handleSelectPage(node.data.id)
+        navigate(`${baseLogos}?page=${encodeURIComponent(node.data.id)}`)
+      }
+    },
+    [handleSelectPage, node.data.id, baseLogos, navigate, node.state.isEditing, node.state.isDragging]
+  )
+
+  const handleRename = useCallback(() => {
+    node.edit()
+  }, [node])
+
+  const handleDelete = useCallback(() => {
+    const toDelete = new Set<string>()
+    function collectDescendants(id: string) {
+      toDelete.add(id)
+      tree.forEach((p) => {
+        if (p.parentId === id) collectDescendants(p.id)
+      })
+    }
+    collectDescendants(node.data.id)
+    if (recollectionId) {
+      toDelete.forEach((pageId) => {
+        removeLogosPageContent(recollectionId, pageId)
+      })
+    }
+    handleTreeChange(tree.filter((p) => !toDelete.has(p.id)))
+  }, [tree, handleTreeChange, node.data.id, recollectionId])
+
+  const handleAddChild = useCallback(() => {
+    const maxPos = Math.max(
+      0,
+      ...tree.filter((p) => p.parentId === node.data.id).map((p) => p.position),
+      -1
+    )
+    const newPage: LogosPageMeta = {
+      id: `page-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`,
+      title: 'Untitled',
+      parentId: node.data.id,
+      position: maxPos + 1,
+    }
+    handleTreeChange([...tree, newPage])
+    if (!node.isOpen) node.open()
+  }, [tree, handleTreeChange, node])
+
+  const hasChildren = (node.children?.length || 0) > 0
+  const pageTitle = node.data.title || 'Untitled'
+
+  return (
+    <div className="flex min-w-0 flex-1 items-center gap-1">
+      {/* Floating drag pill: expands on row hover; coarse pointers keep it tappable */}
+      <div
+        className={cn(
+          'flex shrink-0 items-center justify-center overflow-hidden',
+          'transition-[width,opacity] duration-200 ease-out',
+          'w-0 opacity-0 group-hover:w-4 group-hover:opacity-100',
+          '[@media(pointer:coarse)]:w-5 [@media(pointer:coarse)]:opacity-100',
+          node.state.isDragging && 'w-4 opacity-100 [@media(pointer:coarse)]:w-5',
+          node.state.isEditing && 'pointer-events-none w-0 opacity-0'
+        )}
+      >
+        <div
+          ref={dragHandle}
+          style={{ ...style, paddingLeft: 0 }}
+          title={node.state.isEditing ? undefined : 'Drag to reorder'}
+          className={cn(
+            'logos-tree-drag-handle group/drag',
+            'relative flex h-6 w-4 shrink-0 touch-none items-center justify-center rounded-md',
+            '[@media(pointer:coarse)]:h-7 [@media(pointer:coarse)]:w-5',
+            'border border-sidebar-border/50 bg-sidebar-accent/40',
+            'text-sidebar-foreground/70',
+            'transition-[color,background-color,border-color,box-shadow,transform] duration-150 ease-out',
+            'hover:border-sidebar-border hover:bg-sidebar-accent hover:text-sidebar-accent-foreground',
+            'hover:shadow-sm',
+            'active:scale-[0.97] active:cursor-grabbing',
+            'cursor-grab outline-none',
+            'dark:border-sidebar-border/55 dark:bg-sidebar-accent/35 dark:text-sidebar-foreground/75',
+            'dark:hover:bg-sidebar-accent dark:hover:text-sidebar-accent-foreground',
+            node.state.isDragging &&
+              'cursor-grabbing border-primary/55 bg-primary/18 text-primary shadow-sm ring-1 ring-primary/30 dark:border-primary/50 dark:bg-primary/22 dark:text-primary'
+          )}
+          onClick={(e) => e.stopPropagation()}
+        >
+          <GripVertical
+            className={cn(
+              'size-3 shrink-0 text-current transition-opacity duration-150 opacity-85 group-hover/drag:opacity-100',
+              node.state.isDragging && 'opacity-100'
+            )}
+            strokeWidth={2}
+          />
+        </div>
+      </div>
+
+      {hasChildren ? (
+        <button
+          type="button"
+          className="shrink-0 p-0.5 hover:bg-sidebar-accent rounded transition-colors"
+          onClick={handleToggle}
+        >
+          {node.isOpen ? (
+            <ChevronDown className="size-3.5 text-sidebar-foreground/70" />
+          ) : (
+            <ChevronRight className="size-3.5 text-sidebar-foreground/70" />
+          )}
+        </button>
+      ) : (
+        <div className="w-4 shrink-0" />
+      )}
+
+      <div
+        className={cn(
+          'flex min-h-[28px] min-w-0 flex-1 items-center gap-1 rounded-md px-0.5 -mx-0.5',
+          node.state.isEditing ? 'cursor-text' : 'cursor-pointer hover:bg-sidebar-accent/40'
+        )}
+        onClick={handleSelect}
+      >
+        <FileText className="size-4 shrink-0 text-sidebar-foreground/70" />
+
+        <div className="min-w-0 flex-1">
+          {node.state.isEditing ? (
+            <EditableTitle
+              title={node.data.title}
+              onSave={(newTitle) => {
+                if (newTitle.trim()) {
+                  handleTreeChange(
+                    tree.map((p) => (p.id === node.data.id ? { ...p, title: newTitle.trim() } : p))
+                  )
+                }
+                node.submit(newTitle)
+              }}
+              onCancel={() => node.reset()}
+            />
+          ) : (
+            <span className="block truncate select-none">{pageTitle}</span>
+          )}
+        </div>
+      </div>
+
+      <div
+        className="flex shrink-0 items-center gap-0.5 opacity-0 transition-opacity group-hover:opacity-100"
+        onPointerDown={(e) => e.stopPropagation()}
+      >
+        <button
+          type="button"
+          className="p-0.5 hover:bg-sidebar-accent rounded transition-colors"
+          onClick={(e) => {
+            e.stopPropagation()
+            handleAddChild()
+          }}
+          title="Add child page"
+        >
+          <Plus className="size-3.5 text-sidebar-foreground/70" />
+        </button>
+        <DropdownMenu>
+          <DropdownMenuTrigger asChild>
+            <button
+              type="button"
+              className="p-0.5 hover:bg-sidebar-accent rounded transition-colors"
+              onClick={(e) => e.stopPropagation()}
+            >
+              <MoreHorizontal className="size-3.5 text-sidebar-foreground/70" />
+            </button>
+          </DropdownMenuTrigger>
+          <DropdownMenuContent align="end" className="w-40" onClick={(e) => e.stopPropagation()}>
+            <DropdownMenuItem onClick={handleRename}>
+              <Pencil className="mr-2 size-3.5" />
+              Rename
+            </DropdownMenuItem>
+            <DropdownMenuSeparator />
+            <DropdownMenuItem onClick={handleDelete} className="text-destructive focus:text-destructive">
+              <Trash2 className="mr-2 size-3.5" />
+              Delete
+            </DropdownMenuItem>
+          </DropdownMenuContent>
+        </DropdownMenu>
+      </div>
+    </div>
+  )
+}
+
+/** Drop target + layout shell; `children` must be the Node renderer (drag layer). */
+function TreeRow({ node, innerRef, attrs, children }: RowRendererProps<TreeNode>) {
+  const { pathname } = useLocation()
+  const { activePageId } = useRecollectionSidebar()
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const base = recollectionId ? `/recollections/${recollectionId}` : ''
+  const baseLogos = `${base}/logos`
+  const isActive = pathname.startsWith(baseLogos) && activePageId === node.data.id
+  const level = node.level
+  const indentPx = ROW_GUTTER_PX + level * ROW_INDENT_PX
+
+  return (
+    <div
+      ref={innerRef}
+      {...attrs}
+      style={{
+        ...attrs.style,
+        paddingLeft: `${indentPx}px`,
+      }}
+      className={cn(
+        'group relative flex items-center gap-1 py-1 pr-2 text-sm rounded-md transition-[box-shadow,background-color,ring-color] duration-150',
+        'hover:bg-sidebar-accent hover:text-sidebar-accent-foreground',
+        isActive && 'bg-sidebar-accent text-sidebar-accent-foreground',
+        node.state.isDragging && 'cursor-grabbing opacity-45',
+        // Folder drop target: index === null in library — reads as “open container”, not a line between rows
+        node.state.willReceiveDrop &&
+          'cursor-copy bg-sidebar-accent/30 ring-2 ring-inset ring-dashed ring-sidebar-ring/80 shadow-[inset_0_0_0_1px_hsl(var(--sidebar-border))]'
+      )}
+      title={node.state.willReceiveDrop ? 'Release to drop inside this folder' : undefined}
+    >
+      {level > 0 && (
+        <div
+          className="pointer-events-none absolute bottom-0 top-0 border-l-2 border-sidebar-border/45"
+          style={{ left: `${ROW_GUTTER_PX + (level - 1) * ROW_INDENT_PX + ROW_INDENT_PX / 2}px` }}
+        />
+      )}
+      {children}
+    </div>
+  )
+}
+
+export function TreeBrowser() {
+  const { tree, handleTreeChange } = useRecollectionSidebar()
+  const [searchQuery, setSearchQuery] = useState('')
+  const treeRef = useRef<TreeApi<TreeNode> | null>(null)
+  const [treeContainerHeight, treeContainerRef] = useResizeHeight(600)
+
+  // Build tree from flat structure
+  const treeNodes = useTreeNodes(tree)
+
+  // Filter tree based on search query
+  const filteredTree = useMemo(() => {
+    if (!searchQuery.trim()) return treeNodes
+
+    const searchTerm = searchQuery.toLowerCase()
+
+    function filterNodes(nodes: TreeNode[]): TreeNode[] {
+      const result: TreeNode[] = []
+      for (const node of nodes) {
+        const matches = node.title.toLowerCase().includes(searchTerm)
+        const children = filterNodes(node.children || [])
+
+        if (matches || children.length > 0) {
+          result.push({
+            ...node,
+            children: children.length > 0 ? children : undefined,
+          })
+        }
+      }
+      return result
+    }
+
+    return filterNodes(treeNodes)
+  }, [treeNodes, searchQuery])
+
+  // Get all folder IDs for initial open state
+  const initialOpenState = useMemo(() => {
+    const folderIds: Record<string, boolean> = {}
+    function collectIds(nodes: TreeNode[]) {
+      nodes.forEach((node) => {
+        if (node.isFolder) {
+          folderIds[node.id] = true
+          collectIds(node.children || [])
+        }
+      })
+    }
+    collectIds(treeNodes)
+    return folderIds
+  }, [treeNodes])
+
+  // Handle drag and drop reordering (react-arborist onMove)
+  const handleMove = useCallback(
+    ({
+      dragIds,
+      parentId: newParentId,
+      index,
+    }: {
+      dragIds: string[]
+      parentId: string | null
+      index: number
+    }) => {
+      const dragId = dragIds[0]
+      if (!dragId) return
+
+      const dragged = tree.find((p) => p.id === dragId)
+      if (!dragged) return
+
+      const oldParentId = dragged.parentId
+      const moved: LogosPageMeta = { ...dragged, parentId: newParentId }
+
+      const newSiblings = tree
+        .filter((p) => p.parentId === newParentId && p.id !== dragId)
+        .sort((a, b) => a.position - b.position)
+      newSiblings.splice(index, 0, moved)
+
+      const updates = new Map<string, LogosPageMeta>()
+      newSiblings.forEach((p, i) => {
+        updates.set(p.id, { ...p, parentId: newParentId, position: i })
+      })
+
+      if (oldParentId !== newParentId) {
+        tree
+          .filter((p) => p.parentId === oldParentId && p.id !== dragId)
+          .sort((a, b) => a.position - b.position)
+          .forEach((p, i) => {
+            updates.set(p.id, { ...p, position: i })
+          })
+      }
+
+      handleTreeChange(tree.map((p) => updates.get(p.id) ?? p))
+    },
+    [tree, handleTreeChange]
+  )
+
+  // Expand all folders
+  const handleExpandAll = useCallback(() => {
+    treeRef.current?.openAll()
+  }, [])
+
+  // Collapse all folders
+  const handleCollapseAll = useCallback(() => {
+    treeRef.current?.closeAll()
+  }, [])
+
+  // Clear search
+  const handleClearSearch = useCallback(() => {
+    setSearchQuery('')
+  }, [])
+
+  // Fixed prop shape: react-arborist TreeProvider uses [...Object.values(treeProps), …] as useMemo deps;
+  // varying key counts on the props object trigger "dependency array changed size" warnings.
+  const arboristTreeProps = useMemo(
+    () => ({
+      data: filteredTree,
+      idAccessor: 'id' as const,
+      childrenAccessor: 'children' as const,
+      width: '100%' as const,
+      height: Math.max(treeContainerHeight, 100),
+      rowHeight: 32,
+      indent: ROW_INDENT_PX,
+      renderRow: TreeRow,
+      initialOpenState,
+      onMove: handleMove,
+      disableDrag: Boolean(searchQuery),
+      disableDrop: Boolean(searchQuery),
+      className: 'react-arborist-tree',
+      renderCursor: LogosDropCursor,
+      children: LogosTreeNode,
+    }),
+    [filteredTree, initialOpenState, handleMove, searchQuery, treeContainerHeight]
+  )
+
+  return (
+    <div className="flex flex-col gap-2 h-full">
+      {/* Search Toolbar */}
+      <div className="flex items-center gap-1.5">
+        <div className="relative flex-1">
+          <Search className="absolute left-2 top-1/2 -translate-y-1/2 size-3.5 text-sidebar-foreground/50 pointer-events-none" />
+          <Input
+            type="text"
+            placeholder="Search pages..."
+            value={searchQuery}
+            onChange={(e) => setSearchQuery(e.target.value)}
+            className="pl-7 pr-7 h-7 text-xs bg-sidebar-accent/50 border-sidebar-border"
+          />
+          {searchQuery && (
+            <Button
+              type="button"
+              variant="ghost"
+              size="icon"
+              className="absolute right-0 top-1/2 -translate-y-1/2 h-7 w-7"
+              onClick={handleClearSearch}
+            >
+              <X className="size-3" />
+            </Button>
+          )}
+        </div>
+        <DropdownMenu>
+          <DropdownMenuTrigger asChild>
+            <Button
+              type="button"
+              variant="ghost"
+              size="icon"
+              className="h-7 w-7 shrink-0"
+              title="Expand/Collapse options"
+            >
+              <ChevronsUpDown className="size-3.5" />
+            </Button>
+          </DropdownMenuTrigger>
+          <DropdownMenuContent align="end">
+            <DropdownMenuItem onClick={handleExpandAll}>
+              <ChevronsDownUp className="mr-2 size-3.5" />
+              Expand all
+            </DropdownMenuItem>
+            <DropdownMenuItem onClick={handleCollapseAll}>
+              <ChevronsUpDown className="mr-2 size-3.5" />
+              Collapse all
+            </DropdownMenuItem>
+          </DropdownMenuContent>
+        </DropdownMenu>
+      </div>
+
+      {/* Tree */}
+      <div ref={treeContainerRef} className="flex-1 min-h-0 overflow-hidden">
+        <Tree ref={treeRef} {...arboristTreeProps} />
+      </div>
+    </div>
+  )
+}

frontend/src/app/recollections/layout/recollectionNav.ts

@@ -0,0 +1,25 @@
+/**
+ * Recollection navigation helpers: current view mode from pathname, labels for breadcrumbs.
+ */
+
+export type RecollectionViewMode = 'logos' | 'katalogos' | 'flux'
+
+export function getMode(pathname: string): RecollectionViewMode {
+  if (pathname.endsWith('/flux')) return 'flux'
+  if (pathname.endsWith('/logos/katalogos')) return 'katalogos'
+  return 'logos'
+}
+
+export function viewLabel(mode: RecollectionViewMode): string {
+  if (mode === 'katalogos') return 'Katalogos'
+  if (mode === 'flux') return 'Flux'
+  return 'Logos'
+}
+
+export const RECOLLECTION_VIEW_MODES: RecollectionViewMode[] = ['logos', 'katalogos', 'flux']
+
+export function pathForMode(base: string, mode: RecollectionViewMode): string {
+  if (mode === 'flux') return `${base}/flux`
+  if (mode === 'katalogos') return `${base}/logos/katalogos`
+  return `${base}/logos`
+}

frontend/src/app/recollections/logos/LogosPage.tsx

@@ -0,0 +1,214 @@
+/**
+ * Logos page: BlockNote editor for the recollection. Content only; sidebar is at layout level.
+ * Content persisted in recollection store.
+ */
+
+import React, { useCallback, useEffect, useMemo, useRef, useState, forwardRef } from 'react'
+import { useParams, useLocation, useSearchParams } from 'react-router-dom'
+import { usePlatform } from '@/app/kosmos/KosmosContext'
+import { FluxIcon } from '@/lib/icons'
+import { useCreateBlockNote, getDefaultReactSlashMenuItems, SuggestionMenuController } from '@blocknote/react'
+import { BlockNoteView } from '@blocknote/shadcn'
+import { useTheme } from '@/lib/themeContext'
+import { useRecollectionActions } from '../layout/RecollectionActionsContext'
+import { useRecollectionSidebar } from '../layout/RecollectionSidebarContext'
+import {
+  getLogosContentForPage,
+  setLogosContentForPage,
+  type StoredLogosContent,
+} from '../state/recollectionStore'
+import { logosSchema } from './logosSchema'
+import { KatalogosPage } from '../katalogos/KatalogosPage'
+import { toast } from 'sonner'
+
+/** Wraps BlockNoteView so refs go to a div, not the function component (avoids ref warning). */
+const BlockNoteViewWrapper = forwardRef<HTMLDivElement, React.ComponentProps<typeof BlockNoteView>>(
+  function BlockNoteViewWrapper(props, ref) {
+    const { className, ref: _ref, ...rest } = props as React.ComponentProps<typeof BlockNoteView> & { ref?: unknown }
+    return (
+      <div ref={ref} className={`logos-blocknote ${className ?? ''}`} style={{ minHeight: '100%', width: '100%' }}>
+        <BlockNoteView {...rest} />
+      </div>
+    )
+  }
+)
+const SAVE_DEBOUNCE_MS = 400
+
+/** Known React ref warning from BlockNote/Radix internals; we can't fix it in our code. Suppress once at load so it's active before first BlockNote render. */
+function isBlockNoteRefWarning(args: unknown[]): boolean {
+  const s = args.map((a) => (typeof a === 'string' ? a : String(a))).join(' ')
+  return (
+    s.includes('Function components cannot be given refs') &&
+    s.includes('ForwardRef') &&
+    s.includes('blocknote')
+  )
+}
+let blockNoteRefWarningPatched = false
+function patchBlockNoteRefWarning() {
+  if (blockNoteRefWarningPatched) return
+  blockNoteRefWarningPatched = true
+  const orig = console.error
+  console.error = (...args: unknown[]) => {
+    if (isBlockNoteRefWarning(args)) return
+    orig.apply(console, args)
+  }
+}
+
+export function LogosPage() {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const { pathname } = useLocation()
+  const [searchParams, setSearchParams] = useSearchParams()
+  const { recollections } = usePlatform()
+  const { theme } = useTheme()
+  const { setLogosSlot } = useRecollectionActions()
+  const { tree, activePageId } = useRecollectionSidebar()
+  const recollection = recollectionId ? recollections.find((p) => p.id === recollectionId) : null
+  const [reloadKey, setReloadKey] = useState(0)
+  const saveTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const [saveStatus, setSaveStatus] = useState<'saved' | 'unsaved' | 'saving'>('saved')
+
+  const isKatalogosView = pathname.endsWith('/logos/katalogos')
+
+  // When on Logos (not Katalogos) with a selected page but no page param, sync URL so refresh keeps the page.
+  useEffect(() => {
+    if (isKatalogosView || !activePageId || searchParams.get('page') === activePageId) return
+    setSearchParams({ page: activePageId }, { replace: true })
+  }, [isKatalogosView, activePageId, searchParams, setSearchParams])
+
+  const initialContent = useMemo(() => {
+    if (!recollectionId || !activePageId) return undefined
+    const content = getLogosContentForPage(recollectionId, activePageId)
+    if (!content || !Array.isArray(content) || content.length === 0) return undefined
+    return content
+  }, [recollectionId, activePageId, reloadKey])
+
+  const editor = useCreateBlockNote(
+    { schema: logosSchema, initialContent },
+    [recollectionId, activePageId, reloadKey]
+  )
+
+  const persistContent = useCallback(() => {
+    if (!recollectionId || !activePageId || !editor) return
+    setSaveStatus('saving')
+    try {
+      const doc = editor.document
+      const serialized = JSON.parse(JSON.stringify(doc)) as StoredLogosContent
+      setLogosContentForPage(recollectionId, activePageId, serialized)
+      setSaveStatus('saved')
+    } catch {
+      setSaveStatus('unsaved')
+    }
+  }, [recollectionId, activePageId, editor])
+
+  const onSave = useCallback(() => {
+    persistContent()
+    toast.success('Saved')
+  }, [persistContent])
+
+  useEffect(() => {
+    if (!editor || !recollectionId || !activePageId) return
+    const handleChange = () => {
+      setSaveStatus('unsaved')
+      if (saveTimeoutRef.current) clearTimeout(saveTimeoutRef.current)
+      saveTimeoutRef.current = setTimeout(() => {
+        saveTimeoutRef.current = null
+        persistContent()
+      }, SAVE_DEBOUNCE_MS)
+    }
+    editor.onChange(handleChange)
+    return () => {
+      if (saveTimeoutRef.current) {
+        clearTimeout(saveTimeoutRef.current)
+        saveTimeoutRef.current = null
+      }
+    }
+  }, [editor, recollectionId, activePageId, persistContent])
+
+  useEffect(() => {
+    if (isKatalogosView || !editor || !recollectionId || !activePageId) {
+      if (isKatalogosView) setLogosSlot(null)
+      return
+    }
+    const slot = {
+      saveStatus,
+      onSave,
+      canSave: true,
+      undo: () => (editor as { undo?: () => void }).undo?.(),
+      redo: () => (editor as { redo?: () => void }).redo?.(),
+      canUndo: true,
+      canRedo: true,
+      onRefreshFromStore: () => setReloadKey((k) => k + 1),
+    }
+    setLogosSlot(slot)
+    return () => setLogosSlot(null)
+  }, [isKatalogosView, setLogosSlot, saveStatus, onSave, editor, recollectionId, activePageId])
+
+  const activePage = tree.find((p) => p.id === activePageId)
+
+  patchBlockNoteRefWarning()
+
+  const getSlashMenuItems = useCallback(
+    async (query: string) => {
+      const defaultItems = getDefaultReactSlashMenuItems(editor)
+      const fluxItem = {
+        title: 'Insert Artifact',
+        subtext: 'Insert an Artifact produced by a Flux rendering node',
+        icon: <FluxIcon className="size-4" />,
+        onItemClick: () => {
+          const pos = editor.getTextCursorPosition()
+          editor.replaceBlocks([pos.block.id], [{ type: 'fluxOutput', props: {} }])
+        },
+        aliases: ['artifact', 'flux', 'output', 'render'] as const,
+        group: 'Artifacts',
+      }
+      const all = [...defaultItems, fluxItem]
+      const q = query.trim().toLowerCase()
+      if (!q) return all
+      return all.filter(
+        (item) =>
+          item.title.toLowerCase().includes(q) ||
+          (item.aliases && item.aliases.some((a: string) => a.toLowerCase().includes(q)))
+      )
+    },
+    [editor]
+  )
+
+  if (!recollectionId) {
+    return (
+      <div className="flex h-full min-h-0 flex-1 flex-col items-center justify-center p-8 text-muted-foreground">
+        <p className="text-sm">No recollection selected.</p>
+      </div>
+    )
+  }
+
+  if (isKatalogosView) {
+    return (
+      <div className="flex h-full min-h-0 flex-1 flex-col overflow-auto bg-background">
+        <KatalogosPage />
+      </div>
+    )
+  }
+
+  if (activePageId == null || !editor) {
+    return (
+      <div className="flex h-full min-h-0 flex-1 flex-col items-center justify-center bg-background text-sm text-muted-foreground">
+        {tree.length === 0 ? 'Loading…' : 'Select a page'}
+      </div>
+    )
+  }
+
+  return (
+    <div className="flex h-full min-h-0 flex-1 flex-col overflow-auto bg-background">
+      <div className="mx-auto w-full max-w-3xl p-4">
+        <BlockNoteViewWrapper
+          editor={editor as any}
+          theme={theme}
+          className="min-h-full w-full"
+          slashMenu={false}
+        >
+          <SuggestionMenuController triggerCharacter="/" getItems={getSlashMenuItems} />
+        </BlockNoteViewWrapper>
+      </div>
+    </div>
+  )
+}

frontend/src/app/recollections/logos/blocks/fluxOutputBlock.tsx

@@ -0,0 +1,200 @@
+/**
+ * BlockNote block "Flux output": insert Artifacts produced by Flux rendering nodes into Logos.
+ * Empty state: placeholder + picker over getRenderOutputCache(recollectionId).
+ * Filled state: when nodeId is set, display is live from the cache (updates when the rendering node changes in Flux);
+ * otherwise or when cache entry is missing, show stored content (static).
+ * Shows live/static status and time since last update.
+ */
+
+import React, { useCallback, useState } from 'react'
+import { useNavigate, useParams } from 'react-router-dom'
+import { createReactBlockSpec } from '@blocknote/react'
+import type { ReactCustomBlockRenderProps } from '@blocknote/react'
+import {
+  getRenderOutputCache,
+  formatTimeSinceLastUpdate,
+  type RenderOutputCacheEntry,
+} from '../../state/recollectionStore'
+import { Button } from '@/components/ui/button'
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover'
+
+const fluxOutputBlockConfig = {
+  type: 'fluxOutput' as const,
+  propSchema: {
+    nodeId: {
+      default: '',
+    },
+    contentType: {
+      default: 'image' as const,
+      values: ['image', 'html'] as const,
+    },
+    content: {
+      default: '',
+    },
+    label: {
+      default: '',
+    },
+  },
+  content: 'none' as const,
+}
+
+function FluxOutputBlockContent({
+  block,
+  editor,
+  contentRef,
+}: ReactCustomBlockRenderProps<'fluxOutput', typeof fluxOutputBlockConfig.propSchema, 'none'>) {
+  const { recollectionId } = useParams<{ recollectionId: string }>()
+  const navigate = useNavigate()
+  const [pickerOpen, setPickerOpen] = useState(false)
+  const nodeId = block.props.nodeId ?? ''
+  const storedContent = block.props.content ?? ''
+  const storedContentType = block.props.contentType ?? 'image'
+  const storedLabel = block.props.label ?? ''
+
+  const handleSelect = useCallback(
+    (entry: RenderOutputCacheEntry) => {
+      editor.updateBlock(block.id, {
+        props: {
+          nodeId: entry.nodeId,
+          contentType: entry.type,
+          content: entry.content,
+          label: entry.label,
+        },
+      })
+      setPickerOpen(false)
+    },
+    [editor, block.id]
+  )
+
+  const artifacts = recollectionId ? getRenderOutputCache(recollectionId) : []
+
+  // Resolve display from cache when block is tied to a node (live); otherwise use stored props (static).
+  const liveEntry = nodeId && recollectionId ? artifacts.find((e) => e.nodeId === nodeId) : null
+  const content = liveEntry ? liveEntry.content : storedContent
+  const rawContentType = liveEntry ? liveEntry.type : storedContentType
+  const label = liveEntry ? liveEntry.label : storedLabel
+  const isLive = Boolean(liveEntry)
+  const timeSince = liveEntry?.updatedAt != null ? formatTimeSinceLastUpdate(liveEntry.updatedAt) : ''
+  // If content is SVG but type was stored as html, show as image (fixes incorrect cache or legacy data).
+  const isSvgContent = Boolean(content?.trim() && /<svg[\s>]/i.test(content.trim()))
+  const contentType = rawContentType === 'image' || isSvgContent ? 'image' : 'html'
+
+  const handleViewInFlux = useCallback(() => {
+    if (recollectionId && nodeId) {
+      navigate(`/recollections/${recollectionId}/flux?focusNode=${encodeURIComponent(nodeId)}`)
+    }
+  }, [recollectionId, nodeId, navigate])
+
+  // Empty: show placeholder + picker when nothing inserted yet
+  if (!content) {
+    return (
+      <div
+        ref={contentRef}
+        className="min-h-[80px] rounded-lg border border-dashed border-muted-foreground/30 bg-muted/20 p-4"
+      >
+        <Popover open={pickerOpen} onOpenChange={setPickerOpen}>
+          <PopoverTrigger asChild>
+            <Button variant="outline" size="sm" className="gap-2">
+              Insert Artifact
+            </Button>
+          </PopoverTrigger>
+          <PopoverContent className="w-80 p-0" align="start">
+            {artifacts.length === 0 ? (
+              <div className="p-4 text-sm text-muted-foreground">
+                No Artifacts yet. In Flux, run a graph with a rendering node; its output will be cached as an Artifact
+                and appear here and in Katalogos automatically.
+              </div>
+            ) : (
+              <ul className="max-h-64 overflow-auto py-2">
+                {artifacts.map((entry) => (
+                  <li key={entry.nodeId}>
+                    <button
+                      type="button"
+                      className="w-full px-4 py-2 text-left text-sm hover:bg-muted"
+                      onClick={() => handleSelect(entry)}
+                    >
+                      {entry.label || entry.nodeId}
+                      <span className="ml-2 text-muted-foreground">({entry.type})</span>
+                    </button>
+                  </li>
+                ))}
+              </ul>
+            )}
+          </PopoverContent>
+        </Popover>
+      </div>
+    )
+  }
+
+  // Filled: card layout with header (label + live/static status + time) and content
+  const header = (
+    <div className="flex flex-wrap items-center justify-between gap-2 border-b border-border/60 bg-muted/30 px-3 py-1.5 rounded-t-lg">
+      <div className="flex min-w-0 items-center gap-2">
+        {label ? <span className="truncate text-xs font-medium text-foreground">{label}</span> : null}
+        <span
+          className={
+            isLive
+              ? 'inline-flex items-center gap-1 rounded-full bg-emerald-500/10 px-1.5 py-0.5 text-[10px] font-medium uppercase tracking-wide text-emerald-600 dark:text-emerald-400'
+              : 'inline-flex items-center gap-1 rounded-full bg-muted px-1.5 py-0.5 text-[10px] font-medium uppercase tracking-wide text-muted-foreground'
+          }
+        >
+          {isLive && <span className="h-1 w-1 shrink-0 rounded-full bg-emerald-500" aria-hidden />}
+          {isLive ? 'Live' : 'Static'}
+        </span>
+        {timeSince ? (
+          <span className="text-[10px] text-muted-foreground">{timeSince}</span>
+        ) : null}
+      </div>
+      {nodeId && recollectionId ? (
+        <Button
+          type="button"
+          variant="ghost"
+          size="sm"
+          className="h-6 px-2 text-[10px] text-muted-foreground hover:text-foreground"
+          onClick={handleViewInFlux}
+        >
+          View in Flux
+        </Button>
+      ) : null}
+    </div>
+  )
+
+  if (contentType === 'image') {
+    const src =
+      content.startsWith('data:') ? content : `data:image/svg+xml;utf8,${encodeURIComponent(content)}`
+    return (
+      <div
+        ref={contentRef}
+        className="min-h-[40px] overflow-hidden rounded-lg border border-border bg-card text-card-foreground shadow-sm"
+      >
+        {header}
+        <div className="p-2">
+          <img src={src} alt={label || 'Artifact'} className="max-w-full rounded-md border border-border/60 object-contain" />
+        </div>
+      </div>
+    )
+  }
+
+  // HTML: render in iframe to limit script execution (XSS safety)
+  return (
+    <div
+      ref={contentRef}
+      className="min-h-[40px] overflow-hidden rounded-lg border border-border bg-card text-card-foreground shadow-sm"
+    >
+      {header}
+      <div className="p-2">
+        <iframe
+          title={label || 'Artifact HTML'}
+          srcDoc={content}
+          className="min-h-[120px] w-full rounded-md border border-border/60 bg-background"
+          sandbox="allow-same-origin"
+        />
+      </div>
+    </div>
+  )
+}
+
+export const createFluxOutputBlock = () =>
+  createReactBlockSpec(fluxOutputBlockConfig, {
+    render: FluxOutputBlockContent,
+  })

frontend/src/app/recollections/logos/logosSchema.ts

@@ -0,0 +1,17 @@
+/**
+ * BlockNote schema for Logos: default blocks + Flux output block.
+ */
+
+import { BlockNoteSchema, defaultBlockSpecs } from '@blocknote/core'
+import { createFluxOutputBlock } from './blocks/fluxOutputBlock'
+
+const fluxOutputBlock = createFluxOutputBlock()
+
+export const logosSchema = BlockNoteSchema.create({
+  blockSpecs: {
+    ...defaultBlockSpecs,
+    fluxOutput: fluxOutputBlock,
+  },
+})
+
+export type LogosSchema = typeof logosSchema

frontend/src/app/recollections/state/recollectionGraphStorage.ts

@@ -0,0 +1,24 @@
+/**
+ * Per-recollection graph persistence. Re-exports from recollectionStore for backward compatibility.
+ * New code should use recollectionStore (getGraph, setGraph, removeRecollectionData) directly.
+ */
+
+import {
+  getGraph,
+  setGraph,
+  removeRecollectionData,
+  RECOLLECTION_FILE_EXT,
+  RECOLLECTION_VERSION,
+  type StoredGraphState,
+} from './recollectionStore'
+
+export type { StoredGraphState }
+export { RECOLLECTION_FILE_EXT, RECOLLECTION_VERSION }
+
+export function getGraphStorageKey(recollectionId: string): string {
+  return `zui_graph_${recollectionId}`
+}
+
+export const loadGraphFromStorage = getGraph
+export const saveGraphToStorage = setGraph
+export const removeGraphFromStorage = removeRecollectionData

frontend/src/app/recollections/state/recollectionStore.ts

@@ -0,0 +1,283 @@
+/**
+ * Per-recollection persistence: graph (Flux) and logos (BlockNote) state.
+ * Single API for loading, saving, and removing all data for a recollection.
+ */
+
+import type { StoredGraphState } from '@/lib/graph/state'
+
+export type { StoredGraphState }
+
+/** BlockNote document: array of blocks (PartialBlock). Stored as JSON. */
+export type StoredLogosContent = Record<string, unknown>[]
+
+/** Id for a Logos page or subpage. */
+export type LogosPageId = string
+
+/** Metadata for one page or subpage in the Logos hierarchy (one level: page → subpages). */
+export type LogosPageMeta = {
+  id: LogosPageId
+  title: string
+  /** null = top-level page; non-null = subpage under that page. */
+  parentId: LogosPageId | null
+  /** Order among siblings (same parent). */
+  position: number
+}
+
+/** One entry in the render-output cache (one per rendering node, overwritten on each update). */
+export type RenderOutputCacheEntry = {
+  nodeId: string
+  label: string
+  type: 'image' | 'html'
+  content: string
+  /** Timestamp (ms) when this entry was last updated. */
+  updatedAt?: number
+}
+
+/** Returns a short "time since" string for display (e.g. "Just now", "2 min ago"). */
+export function formatTimeSinceLastUpdate(updatedAt: number | undefined): string {
+  if (updatedAt == null || typeof updatedAt !== 'number') return ''
+  const delta = Date.now() - updatedAt
+  if (delta < 15_000) return 'Just now'
+  if (delta < 60_000) return `${Math.round(delta / 1000)}s ago`
+  if (delta < 3600_000) return `${Math.round(delta / 60_000)} min ago`
+  if (delta < 86400_000) return `${Math.round(delta / 3600_000)}h ago`
+  return `${Math.round(delta / 86400_000)}d ago`
+}
+
+export const RECOLLECTION_FILE_EXT = '.zui.json'
+export const RECOLLECTION_VERSION = 1
+
+const GRAPH_KEY_PREFIX = 'zui_graph_'
+const LOGOS_KEY_PREFIX = 'zui_logos_'
+const LOGOS_PAGE_TREE_PREFIX = 'zui_logos_pagetree_'
+const LOGOS_PAGE_CONTENT_PREFIX = 'zui_logos_page_'
+const RENDER_CACHE_KEY_PREFIX = 'zui_render_cache_'
+
+function getGraphKey(recollectionId: string): string {
+  return `${GRAPH_KEY_PREFIX}${recollectionId}`
+}
+
+function getLogosKey(recollectionId: string): string {
+  return `${LOGOS_KEY_PREFIX}${recollectionId}`
+}
+
+function getLogosPageTreeKey(recollectionId: string): string {
+  return `${LOGOS_PAGE_TREE_PREFIX}${recollectionId}`
+}
+
+function getLogosPageContentKey(recollectionId: string, pageId: LogosPageId): string {
+  return `${LOGOS_PAGE_CONTENT_PREFIX}${recollectionId}_${pageId}`
+}
+
+function getRenderCacheKey(recollectionId: string): string {
+  return `${RENDER_CACHE_KEY_PREFIX}${recollectionId}`
+}
+
+// ---------------------------------------------------------------------------
+// Persisted State with Versioning
+// ---------------------------------------------------------------------------
+
+/**
+ * Wrapper for persisted state with version tracking.
+ * Enables schema migrations when the version changes.
+ */
+export type PersistedState<T> = {
+  /** Current schema version. Increment when making breaking changes. */
+  version: number
+  /** The actual data being persisted. */
+  data: T
+  /** Timestamp (ms) when this data was last migrated. */
+  migratedAt?: number
+}
+
+/**
+ * Check if a persisted state has the expected version.
+ * @param state - The persisted state to check
+ * @param expectedVersion - The expected version number
+ * @returns true if versions match, false otherwise
+ */
+export function isVersionMatch<T>(state: PersistedState<T> | null, expectedVersion: number): boolean {
+  return state?.version === expectedVersion
+}
+
+/**
+ * Migrate persisted state to the latest version.
+ * Add migration logic here when changing the schema.
+ * 
+ * @param state - The persisted state to migrate
+ * @returns Migrated state with updated version
+ */
+export function migratePersistedState<T>(state: PersistedState<T>): PersistedState<T> {
+  if (state.version === RECOLLECTION_VERSION) {
+    return state
+  }
+
+  let migratedData = state.data
+  let migratedVersion = state.version
+
+  // Migration 0 -> 1: Initial version with version field
+  if (migratedVersion < 1) {
+    // Data from version 0 already has the correct structure
+    // Just add the version field
+    migratedVersion = 1
+  }
+
+  return {
+    version: migratedVersion,
+    data: migratedData,
+    migratedAt: Date.now(),
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Graph Storage with Versioning
+// ---------------------------------------------------------------------------
+
+export function getGraph(recollectionId: string): StoredGraphState | null {
+  try {
+    const raw = localStorage.getItem(getGraphKey(recollectionId))
+    if (!raw) return null
+    const data = JSON.parse(raw) as unknown
+    if (
+      !data ||
+      typeof data !== 'object' ||
+      !Array.isArray((data as StoredGraphState).nodes) ||
+      !Array.isArray((data as StoredGraphState).edges)
+    )
+      return null
+    return data as StoredGraphState
+  } catch {
+    return null
+  }
+}
+
+export function setGraph(recollectionId: string, state: StoredGraphState): void {
+  localStorage.setItem(getGraphKey(recollectionId), JSON.stringify(state))
+}
+
+// ---------------------------------------------------------------------------
+// Logos Storage
+// ---------------------------------------------------------------------------
+
+export function getLogosContent(recollectionId: string): StoredLogosContent | null {
+  try {
+    const raw = localStorage.getItem(getLogosKey(recollectionId))
+    if (!raw) return null
+    const data = JSON.parse(raw) as unknown
+    if (!Array.isArray(data)) return null
+    if (!data.every((item) => item != null && typeof item === 'object')) return null
+    return data as StoredLogosContent
+  } catch {
+    return null
+  }
+}
+
+export function setLogosContent(recollectionId: string, content: StoredLogosContent): void {
+  localStorage.setItem(getLogosKey(recollectionId), JSON.stringify(content))
+}
+
+/** Logos page tree: ordered list of page metas (pages and subpages). */
+export function getLogosPageTree(recollectionId: string): LogosPageMeta[] {
+  try {
+    const raw = localStorage.getItem(getLogosPageTreeKey(recollectionId))
+    if (!raw) return []
+    const data = JSON.parse(raw) as unknown
+    if (!Array.isArray(data)) return []
+    return data.filter(
+      (item): item is LogosPageMeta =>
+        item != null &&
+        typeof item === 'object' &&
+        typeof (item as LogosPageMeta).id === 'string' &&
+        typeof (item as LogosPageMeta).title === 'string' &&
+        ((item as LogosPageMeta).parentId === null || typeof (item as LogosPageMeta).parentId === 'string') &&
+        typeof (item as LogosPageMeta).position === 'number'
+    ) as LogosPageMeta[]
+  } catch {
+    return []
+  }
+}
+
+export function setLogosPageTree(recollectionId: string, tree: LogosPageMeta[]): void {
+  localStorage.setItem(getLogosPageTreeKey(recollectionId), JSON.stringify(tree))
+}
+
+/** Per-page Logos content (for page/subpage hierarchy). */
+export function getLogosContentForPage(
+  recollectionId: string,
+  pageId: LogosPageId
+): StoredLogosContent | null {
+  try {
+    const raw = localStorage.getItem(getLogosPageContentKey(recollectionId, pageId))
+    if (!raw) return null
+    const data = JSON.parse(raw) as unknown
+    if (!Array.isArray(data)) return null
+    if (!data.every((item) => item != null && typeof item === 'object')) return null
+    return data as StoredLogosContent
+  } catch {
+    return null
+  }
+}
+
+export function setLogosContentForPage(
+  recollectionId: string,
+  pageId: LogosPageId,
+  content: StoredLogosContent
+): void {
+  localStorage.setItem(getLogosPageContentKey(recollectionId, pageId), JSON.stringify(content))
+}
+
+/** Remove stored content for a single page (e.g. when deleting that page). */
+export function removeLogosPageContent(recollectionId: string, pageId: LogosPageId): void {
+  localStorage.removeItem(getLogosPageContentKey(recollectionId, pageId))
+}
+
+// ---------------------------------------------------------------------------
+// Render Output Cache
+// ---------------------------------------------------------------------------
+
+/** Render output cache: one entry per rendering node (keyed by nodeId). Used by Logos "Insert from Flux" block. */
+export function getRenderOutputCache(recollectionId: string): RenderOutputCacheEntry[] {
+  try {
+    const raw = localStorage.getItem(getRenderCacheKey(recollectionId))
+    if (!raw) return []
+    const data = JSON.parse(raw) as unknown
+    if (!Array.isArray(data)) return []
+    return data.filter(
+      (item): item is RenderOutputCacheEntry =>
+        item != null &&
+        typeof item === 'object' &&
+        typeof (item as RenderOutputCacheEntry).nodeId === 'string' &&
+        typeof (item as RenderOutputCacheEntry).label === 'string' &&
+        ((item as RenderOutputCacheEntry).type === 'image' || (item as RenderOutputCacheEntry).type === 'html') &&
+        typeof (item as RenderOutputCacheEntry).content === 'string'
+    ) as RenderOutputCacheEntry[]
+  } catch {
+    return []
+  }
+}
+
+export function upsertRenderOutputEntry(recollectionId: string, entry: RenderOutputCacheEntry): void {
+  const entries = getRenderOutputCache(recollectionId)
+  const byNodeId = new Map(entries.map((e) => [e.nodeId, e]))
+  byNodeId.set(entry.nodeId, entry)
+  localStorage.setItem(
+    getRenderCacheKey(recollectionId),
+    JSON.stringify(Array.from(byNodeId.values()))
+  )
+}
+
+// ---------------------------------------------------------------------------
+// Remove Recollection Data
+// ---------------------------------------------------------------------------
+
+/** Removes both graph, logos (legacy + page tree + all per-page content), and render cache for the recollection. */
+export function removeRecollectionData(recollectionId: string): void {
+  localStorage.removeItem(getGraphKey(recollectionId))
+  localStorage.removeItem(getLogosKey(recollectionId))
+  const tree = getLogosPageTree(recollectionId)
+  for (const page of tree) {
+    removeLogosPageContent(recollectionId, page.id)
+  }
+  localStorage.removeItem(getLogosPageTreeKey(recollectionId))
+  localStorage.removeItem(getRenderCacheKey(recollectionId))
+}

frontend/src/components/editor/CodeEditor.tsx

@@ -0,0 +1,113 @@
+/**
+ * Shared code editor with Nunjucks support by default.
+ * Uses react-simple-code-editor + Prism + prism-react-renderer; highlights base language + {{ }}, {% %}, {# #}.
+ * Wherever this editor is used, it provides the same features (syntax highlighting + Nunjucks).
+ * The parent (node) provides the expected base language for highlighting.
+ */
+import React, { useCallback, useLayoutEffect, useRef } from 'react'
+import Editor from 'react-simple-code-editor'
+import { highlight, type HighlightLanguage } from '@/lib/syntaxHighlight'
+
+export type CodeEditorProps = {
+  value: string
+  onValueChange: (value: string) => void
+  /** Base language for syntax highlighting (Nunjucks is always applied on top). */
+  language: HighlightLanguage
+  /** Stable id for the underlying textarea (for insert-at-cursor). */
+  textareaId?: string
+  readOnly?: boolean
+  placeholder?: string
+  padding?: number
+  tabSize?: number
+  insertSpaces?: boolean
+  ignoreTabKey?: boolean
+  style?: React.CSSProperties
+  className?: string
+  textareaClassName?: string
+  preClassName?: string
+  /** Minimum height so the container doesn't collapse before resize. */
+  minHeight?: number
+}
+
+const defaultStyle: React.CSSProperties = {
+  fontFamily: 'ui-monospace, monospace',
+  fontSize: 12,
+  lineHeight: 1.5,
+  overflow: 'auto',
+}
+
+export function CodeEditor({
+  value,
+  onValueChange,
+  language,
+  textareaId,
+  readOnly = false,
+  padding = 8,
+  tabSize = 2,
+  insertSpaces = true,
+  ignoreTabKey = false,
+  style,
+  className,
+  textareaClassName,
+  preClassName,
+  minHeight = 120,
+}: CodeEditorProps) {
+  const containerRef = useRef<HTMLDivElement | null>(null)
+  const selectionRestoreRef = useRef<{ start: number; end: number } | null>(null)
+
+  const highlightCode = useCallback(
+    (code: string) => highlight(code, language),
+    [language]
+  )
+
+  const handleValueChange = useCallback(
+    (newValue: string) => {
+      if (readOnly) {
+        onValueChange(newValue)
+        return
+      }
+      const ta =
+        (textareaId ? document.getElementById(textareaId) : containerRef.current?.querySelector('textarea')) as HTMLTextAreaElement | null
+      const start = ta?.selectionStart ?? newValue.length
+      const end = ta?.selectionEnd ?? newValue.length
+      selectionRestoreRef.current = { start, end }
+      onValueChange(newValue)
+    },
+    [onValueChange, readOnly, textareaId]
+  )
+
+  useLayoutEffect(() => {
+    const pending = selectionRestoreRef.current
+    if (pending == null) return
+    selectionRestoreRef.current = null
+    const el = (textareaId
+      ? document.getElementById(textareaId)
+      : containerRef.current?.querySelector('textarea')) as HTMLTextAreaElement | null
+    if (el) {
+      const { start, end } = pending
+      const safeEnd = Math.min(end, el.value.length)
+      const safeStart = Math.min(start, safeEnd)
+      el.setSelectionRange(safeStart, safeEnd)
+    }
+  }, [value, textareaId])
+
+  return (
+    <div ref={containerRef} className="code-editor min-h-0 h-full overflow-auto" style={{ minHeight: 0 }}>
+      <Editor
+        value={value}
+        onValueChange={handleValueChange}
+        highlight={highlightCode}
+        tabSize={tabSize}
+        insertSpaces={insertSpaces}
+        ignoreTabKey={ignoreTabKey}
+        padding={padding}
+        readOnly={readOnly}
+        textareaId={textareaId}
+        style={{ ...defaultStyle, minHeight, ...style }}
+        className={className}
+        textareaClassName={textareaClassName}
+        preClassName={preClassName}
+      />
+    </div>
+  )
+}

frontend/src/components/graph/AnimatedEdge.tsx

@@ -1,22 +1,20 @@
-import React, { useContext, useMemo } from 'react'
+import React, { memo } from 'react'
 import {
   BaseEdge,
   getBezierPath,
   type EdgeProps,
 } from '@xyflow/react'
-import FlowContext from '../../lib/flowContext'
+import { useCanvasStore } from '@/app/canvas/canvasStore'
+import { selectConnectionStatusForEdge } from '@/app/canvas/canvasStore.selectors'
+import { CONNECTION_STATUS_CLASS } from '@/lib/graph/connectionStatus'
+import { getConnectionLabelForTargetAndStatus } from '@/lib/graph/nodeRegistry'
 
 const EDGE_STROKE_WIDTH = 2
 const DOT_MARKER_R = 1.5
 
-function getEdgeLabelByTargetType(targetType: string | undefined): string | undefined {
-  if (targetType === 'render') return 'render'
-  if (targetType === 'config' || targetType === 'function') return 'add input'
-  return undefined
-}
-
-export function AnimatedEdge({
+function AnimatedEdgeInner({
   id,
+  source,
   sourceX,
   sourceY,
   targetX,
@@ -27,15 +25,17 @@ export function AnimatedEdge({
   label: labelProp,
   interactionWidth,
   target,
+  data,
 }: EdgeProps) {
-  const ctx = useContext(FlowContext)
-  const nodes = ctx?.nodes ?? []
-  const targetNode = useMemo(() => nodes.find((n: any) => n.id === target), [nodes, target])
-  const derivedLabel = useMemo(
-    () => getEdgeLabelByTargetType(targetNode?.type),
-    [targetNode?.type]
+  const connectionStatus = useCanvasStore((s) =>
+    selectConnectionStatusForEdge(s, source, target)
   )
-  const label = labelProp ?? derivedLabel
+  const statusClass = CONNECTION_STATUS_CLASS[connectionStatus]
+
+  const targetType = (data as { targetType?: string } | undefined)?.targetType ?? ''
+  const dataLabel = (data as { connectionLabel?: string } | undefined)?.connectionLabel
+  const displayLabel =
+    getConnectionLabelForTargetAndStatus(targetType, connectionStatus) ?? labelProp ?? dataLabel
 
   const [edgePath, edgeLabelX, edgeLabelY] = getBezierPath({
     sourceX,
@@ -93,10 +93,10 @@ export function AnimatedEdge({
           strokeWidth: EDGE_STROKE_WIDTH,
           ...style,
         }}
-        className="animated-edge-path"
+        className={`animated-edge-path${statusClass ? ` ${statusClass}` : ''}`}
         interactionWidth={interactionWidth}
       />
-      {label != null && (
+      {displayLabel != null && displayLabel !== '' && (
         <g transform={`translate(${edgeLabelX}, ${edgeLabelY})`} className="nodrag nopan">
           <rect
             x={-32}
@@ -113,10 +113,32 @@ export function AnimatedEdge({
             dominantBaseline="middle"
             className="fill-foreground text-[10px] font-medium"
           >
-            {label}
+            {displayLabel}
           </text>
         </g>
       )}
     </>
   )
 }
+function edgePropsAreEqual(prev: EdgeProps, next: EdgeProps): boolean {
+  return (
+    prev.id === next.id &&
+    prev.source === next.source &&
+    prev.target === next.target &&
+    prev.sourceX === next.sourceX &&
+    prev.sourceY === next.sourceY &&
+    prev.targetX === next.targetX &&
+    prev.targetY === next.targetY &&
+    prev.sourcePosition === next.sourcePosition &&
+    prev.targetPosition === next.targetPosition &&
+    prev.style === next.style &&
+    prev.label === next.label &&
+    (prev.data as { connectionLabel?: string; targetType?: string } | undefined)?.connectionLabel ===
+      (next.data as { connectionLabel?: string; targetType?: string } | undefined)?.connectionLabel &&
+    (prev.data as { targetType?: string } | undefined)?.targetType ===
+      (next.data as { targetType?: string } | undefined)?.targetType
+  )
+}
+
+export const AnimatedEdge = memo(AnimatedEdgeInner, edgePropsAreEqual)
+

frontend/src/components/graph/BaseNode.tsx

@@ -1,10 +1,17 @@
 import type { ComponentProps, ReactNode } from "react";
-import { NodeResizeControl } from "@xyflow/react";
+import { NodeResizer } from "@xyflow/react";
+import { useContext } from "react";
 
+import { FlowUIContext } from "@/lib/graph/flowContext";
+import { useConnectionPathRoleFromStore } from "@/app/canvas/useCanvasConnectionPathFromStore";
 import { cn } from "@/lib/utils";
 
+/** Default min size for resizable nodes (used by NodeResizer). */
+export const RESIZE_MIN_WIDTH = 120;
+export const RESIZE_MIN_HEIGHT = 80;
+
 export type BaseNodeProps = ComponentProps<"div"> & {
-  /** When true, shows a bottom-right resize handle. Requires nodeId when used inside React Flow. */
+  /** When true, shows resize handles on corners/edges (via NodeResizer). Requires nodeId when used inside React Flow. */
   resizable?: boolean;
   /** Node id for the resize control (required when resizable is true). */
   nodeId?: string;
@@ -12,6 +19,10 @@ export type BaseNodeProps = ComponentProps<"div"> & {
   handles?: ReactNode;
   /** When provided, node uses this size (e.g. from React Flow width/height). Enables correct resize behavior. */
   dimensions?: { width: number; height: number };
+  /** When true, node is selected (from React Flow NodeProps). Used for visible selected state. */
+  selected?: boolean;
+  /** Optional min/max for NodeResizer. Omit to use RESIZE_MIN_WIDTH / RESIZE_MIN_HEIGHT. */
+  resizeConstraints?: { minWidth?: number; minHeight?: number; maxWidth?: number; maxHeight?: number };
 };
 
 export function BaseNode({
@@ -22,8 +33,13 @@ export function BaseNode({
   nodeId,
   handles,
   children,
+  selected,
+  resizeConstraints,
   ...props
 }: BaseNodeProps) {
+  const flowUIContext = useContext(FlowUIContext);
+  const isFullscreenInstance = Boolean(nodeId && flowUIContext?.fullscreenNodeId === nodeId);
+  const connectionPathRole = useConnectionPathRoleFromStore(nodeId);
   const hasSize =
     dimensions &&
     dimensions.width > 0 &&
@@ -43,46 +59,49 @@ export function BaseNode({
       ? { ...style, display: "flex", flexDirection: "column" as const }
       : undefined;
 
+  const minW = resizeConstraints?.minWidth ?? RESIZE_MIN_WIDTH;
+  const minH = resizeConstraints?.minHeight ?? RESIZE_MIN_HEIGHT;
+
   return (
     <div
       className={cn(
-        "bg-card text-card-foreground relative rounded-md border",
+        "bg-card text-card-foreground relative rounded-md border transition-[border-color,box-shadow] duration-200",
         "hover:ring-1",
-        // React Flow displays node elements inside of a `NodeWrapper` component,
-        // which compiles down to a div with the class `react-flow__node`.
-        // When a node is selected, the class `selected` is added to the
-        // `react-flow__node` element. This allows us to style the node when it
-        // is selected, using Tailwind's `&` selector.
-        "[.react-flow\\_\\_node.selected_&]:border-muted-foreground",
-        "[.react-flow\\_\\_node.selected_&]:shadow-lg",
+        selected && "border-primary/50 shadow-[0_0_0_2px_hsl(var(--primary)_/_0.15)] dark:border-primary/35 dark:shadow-[0_0_0_2px_hsl(var(--primary)_/_0.1)]",
+        connectionPathRole === "trigger" && "connection-path-trigger",
+        connectionPathRole === "on-path" && "connection-path-on-path",
         className,
       )}
+      data-selected={selected}
+      data-path-role={connectionPathRole ?? undefined}
       style={appliedStyle}
-      tabIndex={0}
+      tabIndex={selected ? 0 : -1}
       {...props}
     >
       <div
-        className="min-h-0 flex-1 flex flex-col overflow-hidden"
+        className={cn(
+          "min-h-0 flex-1 flex flex-col overflow-hidden",
+          !selected && "pointer-events-none",
+        )}
         style={{ contain: "layout" }}
       >
         {children}
       </div>
-      {resizable && nodeId && (
-        <NodeResizeControl
+      {resizable && nodeId && !isFullscreenInstance && (
+        <NodeResizer
           nodeId={nodeId}
-          position="bottom-right"
-          minWidth={120}
-          minHeight={80}
-          className={cn(
-            "!border-0 !bg-transparent !rounded-none !p-0",
-            "absolute bottom-0 right-0 w-8 h-8 cursor-se-resize select-none",
-            "nodrag nopan touch-none",
-          )}
-          style={{ margin: 0, touchAction: "none", userSelect: "none" }}
-        >
-        </NodeResizeControl>
+          isVisible={selected}
+          minWidth={minW}
+          minHeight={minH}
+          maxWidth={resizeConstraints?.maxWidth}
+          maxHeight={resizeConstraints?.maxHeight}
+          color="transparent"
+          handleClassName="base-node-resize-handle nodrag nopan"
+        />
+      )}
+      {!isFullscreenInstance && (
+        <div className={cn(!selected && "pointer-events-none")}>{handles}</div>
       )}
-      {handles}
     </div>
   );
 }
@@ -117,19 +136,37 @@ export function BaseNodeHeaderRow({
   title,
   right,
   className,
+  onHeaderDoubleClick,
 }: {
   icon: ReactNode;
   title: ReactNode;
   /** Optional right-side content (e.g. type selector). */
   right?: ReactNode;
   className?: string;
+  /** When provided, double-click on the header triggers this (e.g. fullscreen). Header gets cursor-pointer and nodrag. */
+  onHeaderDoubleClick?: () => void;
 }) {
   return (
     <header
+      role={onHeaderDoubleClick ? 'button' : undefined}
+      tabIndex={onHeaderDoubleClick ? 0 : undefined}
+      onDoubleClick={onHeaderDoubleClick}
+      onKeyDown={
+        onHeaderDoubleClick
+          ? (e) => {
+            if (e.key === 'Enter' || e.key === ' ') {
+              e.preventDefault();
+              onHeaderDoubleClick();
+            }
+          }
+          : undefined
+      }
       className={cn(
         "shrink-0 mx-0 my-0 flex flex-row items-center justify-between gap-2 px-3 py-2",
+        onHeaderDoubleClick && "cursor-pointer",
         className,
       )}
+      title={onHeaderDoubleClick ? 'Double-click for full screen' : undefined}
     >
       {icon}
       <h3
@@ -166,7 +203,7 @@ export function BaseNodeContent({
   return (
     <div
       data-slot="base-node-content"
-      className={cn("min-h-0 flex-1 flex flex-col overflow-auto", className)}
+      className={cn("min-h-0 flex-1 flex flex-col", className)}
       {...props}
     />
   );
@@ -177,7 +214,7 @@ export function BaseNodeFooter({ className, ...props }: ComponentProps<"div">) {
     <div
       data-slot="base-node-footer"
       className={cn(
-        "shrink-0 flex flex-col items-center gap-y-2 border-t p-1",
+        "shrink-0 flex flex-col items-center gap-y-2 border-t border-border/70 pt-1 px-1 pb-1",
         className,
       )}
       {...props}

frontend/src/components/graph/FlowKeyboardShortcuts.tsx

@@ -0,0 +1,163 @@
+import React, { useCallback, useContext, useEffect } from 'react'
+import { useReactFlow } from '@xyflow/react'
+import type { Node } from '@xyflow/react'
+import { GraphContext, FlowUIContext } from '@/lib/graph/flowContext'
+import { getNextNodeId, getDefaultDataForType } from '@/lib/graph/flowUtils'
+import { getDefaultStyle, getRegisteredNodeTypeIds } from '@/lib/graph/nodeRegistry'
+
+const DUPLICATE_OFFSET = { x: 30, y: 30 }
+
+function isMod(ev: KeyboardEvent) {
+  return ev.ctrlKey || ev.metaKey
+}
+
+/** Must be rendered inside ReactFlowProvider and FlowContext. Handles Escape, ⌘C, ⌘V, ⌘D, ⌘0. */
+export function FlowKeyboardShortcuts() {
+  const { fitView, screenToFlowPosition } = useReactFlow()
+  const graphCtx = useContext(GraphContext)
+  const uiCtx = useContext(FlowUIContext)
+  const setNodes = graphCtx?.setNodes
+  const setConnectionFrom = uiCtx?.setConnectionFrom
+  const flowActionsRef = uiCtx?.flowActionsRef
+
+  const pasteAtViewportCenter = useCallback(async () => {
+    if (!setNodes || !screenToFlowPosition) return
+    try {
+      const text = await navigator.clipboard?.readText()
+      if (!text) return
+      const raw = JSON.parse(text) as {
+        id?: string
+        type?: string
+        data?: Record<string, unknown>
+        position?: { x: number; y: number }
+        style?: unknown
+      }
+      const validIds = getRegisteredNodeTypeIds()
+      if (!raw || typeof raw.type !== 'string' || !validIds.includes(raw.type)) return
+      const nodeType = raw.type
+      const pane = document.querySelector('.react-flow__viewport')
+      const rect = pane?.getBoundingClientRect()
+      const center = rect
+        ? { x: rect.left + rect.width / 2, y: rect.top + rect.height / 2 }
+        : { x: window.innerWidth / 2, y: window.innerHeight / 2 }
+      const position = screenToFlowPosition(center)
+      setNodes((nds: Node[]) => {
+        const existingIds = nds.map((n) => n.id).filter((id): id is string => id != null)
+        const newId = getNextNodeId(nodeType, existingIds)
+        const data: Record<string, unknown> =
+          raw.data != null && typeof raw.data === 'object'
+            ? { ...raw.data }
+            : (getDefaultDataForType(nodeType, newId) as Record<string, unknown>)
+        if (nodeType === 'config') data.title = `config-${newId}`
+        const style = getDefaultStyle(nodeType)
+        const newNode: Node = {
+          id: newId,
+          type: raw.type as Node['type'],
+          position: { x: position.x, y: position.y },
+          data,
+          style,
+        }
+        return nds.concat(newNode)
+      })
+    } catch {
+      // Invalid clipboard or not a copied node
+    }
+  }, [setNodes, screenToFlowPosition])
+
+  const doFitView = useCallback(() => {
+    fitView?.({ duration: 200 })
+  }, [fitView])
+
+  useEffect(() => {
+    if (flowActionsRef) {
+      flowActionsRef.current = { pasteAtViewportCenter, fitView: doFitView }
+      return () => {
+        flowActionsRef.current = null
+      }
+    }
+  }, [flowActionsRef, pasteAtViewportCenter, doFitView])
+
+  useEffect(() => {
+    const onKeyDown = (ev: KeyboardEvent) => {
+      const nodes = graphCtx?.graphRef?.current?.nodes ?? []
+      if (ev.key === 'Escape') {
+        const openDialog = document.querySelector('[role="dialog"]')
+        if (openDialog && ev.target instanceof Node && openDialog.contains(ev.target)) return
+        setConnectionFrom?.(null)
+        setNodes?.((nds) => nds.map((n) => ({ ...n, selected: false })))
+        ev.preventDefault()
+        return
+      }
+      if (ev.key === 'c' && isMod(ev) && !ev.shiftKey) {
+        const selectedNodes = nodes.filter((n) => (n as Node & { selected?: boolean }).selected)
+        if (selectedNodes.length === 1) {
+          const node = selectedNodes[0] as Node & { selected?: boolean }
+          const copy = {
+            id: node.id,
+            type: node.type,
+            data: node.data,
+            position: node.position,
+            style: node.style,
+          }
+          navigator.clipboard?.writeText(JSON.stringify(copy)).catch(() => { })
+          ev.preventDefault()
+        }
+        return
+      }
+      if (ev.key === 'v' && isMod(ev) && !ev.shiftKey) {
+        pasteAtViewportCenter()
+        ev.preventDefault()
+        return
+      }
+      if (ev.key === 'd' && isMod(ev) && !ev.shiftKey) {
+        const selectedNodes = nodes.filter((n) => (n as Node & { selected?: boolean }).selected)
+        if (selectedNodes.length > 0 && setNodes) {
+          setNodes((nds: Node[]) => {
+            const existingIds = nds.map((n) => n.id)
+            const toAdd: Node[] = []
+            for (const node of selectedNodes) {
+              const n = node as Node & { selected?: boolean }
+              const pos = n.position ?? { x: 0, y: 0 }
+              const newId = getNextNodeId(String(n.type), [...existingIds, ...toAdd.map((x) => x.id)])
+              existingIds.push(newId)
+              const newNode: Node = {
+                id: newId,
+                type: n.type,
+                position: { x: pos.x + DUPLICATE_OFFSET.x, y: pos.y + DUPLICATE_OFFSET.y },
+                data: typeof n.data === 'object' && n.data !== null ? { ...(n.data as object) } : n.data,
+                style: getDefaultStyle(String(n.type)),
+              }
+              if (
+                newNode.data &&
+                typeof newNode.data === 'object' &&
+                'title' in newNode.data &&
+                String(n.type) === 'config'
+              ) {
+                ; (newNode.data as Record<string, unknown>).title = `${newId}`
+              }
+              toAdd.push(newNode)
+            }
+            return nds.concat(toAdd)
+          })
+          ev.preventDefault()
+        }
+        return
+      }
+      if (ev.key === '0' && isMod(ev) && !ev.shiftKey) {
+        doFitView()
+        ev.preventDefault()
+        return
+      }
+    }
+    window.addEventListener('keydown', onKeyDown, true)
+    return () => window.removeEventListener('keydown', onKeyDown, true)
+  }, [
+    graphCtx?.graphRef,
+    setNodes,
+    setConnectionFrom,
+    pasteAtViewportCenter,
+    doFitView,
+  ])
+
+  return null
+}

frontend/src/components/graph/NodeFooterEdgeIndicators.tsx

@@ -1,28 +1,17 @@
 import React, { useContext, useMemo } from 'react'
-import FlowContext from '../../lib/flowContext'
+import { GraphContext } from '@/lib/graph/flowContext'
 import { ArrowDownLeft, ArrowUpRight } from 'lucide-react'
-
-const NODE_HAS_INPUT: Record<string, boolean> = {
-    config: true,
-    function: true,
-    render: true,
-    variable: false,
-}
-const NODE_HAS_OUTPUT: Record<string, boolean> = {
-    config: true,
-    function: true,
-    render: true,
-    variable: true,
-}
+import { NodeHelpPopover } from '@/components/graph/NodeHelpPopover'
+import { getNodeType, getNodeClassificationLabel } from '@/lib/graph/nodeRegistry'
 
 type Props = {
     nodeId: string
-    nodeType: 'config' | 'function' | 'render' | 'variable'
+    nodeType: string
     children?: React.ReactNode
 }
 
 export function NodeFooterEdgeIndicators({ nodeId, nodeType, children }: Props) {
-    const ctx = useContext(FlowContext)
+    const ctx = useContext(GraphContext)
     const edges = ctx?.edges ?? []
 
     const { inputs, outputs } = useMemo(() => {
@@ -35,8 +24,10 @@ export function NodeFooterEdgeIndicators({ nodeId, nodeType, children }: Props)
         return { inputs, outputs }
     }, [edges, nodeId])
 
-    const showInput = NODE_HAS_INPUT[nodeType] ?? false
-    const showOutput = NODE_HAS_OUTPUT[nodeType] ?? false
+    const descriptor = getNodeType(nodeType)
+    const showInput = descriptor?.hasInput ?? false
+    const showOutput = descriptor?.hasOutput ?? false
+    const classificationLabel = getNodeClassificationLabel(nodeType)
 
     return (
         <div className="flex items-center gap-2 w-full text-xs text-muted-foreground">
@@ -58,6 +49,15 @@ export function NodeFooterEdgeIndicators({ nodeId, nodeType, children }: Props)
                     <span className="min-w-0 truncate">{children}</span>
                 </>
             )}
+            {classificationLabel != null && (
+                <>
+                    {(showInput || showOutput || children != null) && <span className="shrink-0">|</span>}
+                    <span className="shrink-0" title="Node classification">{classificationLabel}</span>
+                </>
+            )}
+            <span className="shrink-0 ml-auto">
+                <NodeHelpPopover nodeType={nodeType} />
+            </span>
         </div>
     )
 }

frontend/src/components/graph/NodeHandles.tsx

@@ -1,7 +1,7 @@
 import React, { useContext } from 'react'
 import { Handle, Position } from '@xyflow/react'
 import { ArrowDownLeft, ArrowUpRight } from 'lucide-react'
-import FlowContext from '@/lib/flowContext'
+import { FlowUIContext } from '@/lib/graph/flowContext'
 import { cn } from '@/lib/utils'
 
 type NodeHandleProps = {
@@ -11,7 +11,7 @@ type NodeHandleProps = {
 }
 
 export function InputHandle({ id, nodeId }: NodeHandleProps) {
-    const ctx = useContext(FlowContext)
+    const ctx = useContext(FlowUIContext)
     const connectionFrom = ctx?.connectionFrom ?? null
     const isValidConnection = ctx?.isValidConnection
     const isConnecting = Boolean(nodeId && connectionFrom && connectionFrom.nodeId !== nodeId)
@@ -19,7 +19,7 @@ export function InputHandle({ id, nodeId }: NodeHandleProps) {
         isConnecting &&
         isValidConnection?.({
             source: connectionFrom!.nodeId,
-            sourceHandle: connectionFrom!.sourceHandle ?? undefined,
+            sourceHandle: connectionFrom!.sourceHandle ?? null,
             target: nodeId!,
             targetHandle: id,
         })

frontend/src/components/graph/NodeHeaderTitle.tsx

@@ -1,6 +1,7 @@
 import React, { useCallback, useContext, useEffect, useRef, useState } from 'react'
-import FlowContext from '../../lib/flowContext'
-import { replaceNodeIdInGraph } from '../../lib/flowUtils'
+import { GraphContext, FlowUIContext } from '@/lib/graph/flowContext'
+import type { AppNode } from '@/lib/graph/nodeTypes'
+import { replaceNodeIdInGraph } from '@/lib/graph/flowUtils'
 
 type Props = {
     nodeId: string
@@ -8,13 +9,12 @@ type Props = {
 }
 
 export function NodeHeaderTitle({ nodeId, displayTitle }: Props) {
-    const ctx = useContext(FlowContext)
-    const nodes = ctx?.nodes ?? []
-    const setNodes = ctx?.setNodes
-    const edges = ctx?.edges ?? []
-    const setEdges = ctx?.setEdges
-    const renamingNodeId = ctx?.renamingNodeId ?? null
-    const setRenamingNodeId = ctx?.setRenamingNodeId
+    const graphCtx = useContext(GraphContext)
+    const uiCtx = useContext(FlowUIContext)
+    const setNodes = graphCtx?.setNodes
+    const setEdges = graphCtx?.setEdges
+    const renamingNodeId = uiCtx?.renamingNodeId ?? null
+    const setRenamingNodeId = uiCtx?.setRenamingNodeId
 
     const [inputValue, setInputValue] = useState(nodeId)
     const inputRef = useRef<HTMLInputElement>(null)
@@ -30,7 +30,9 @@ export function NodeHeaderTitle({ nodeId, displayTitle }: Props) {
     }, [isRenaming, nodeId])
 
     const applyRename = useCallback(() => {
-        if (!setNodes || !setEdges || !setRenamingNodeId) return
+        if (!setNodes || !setEdges || !setRenamingNodeId || !graphCtx?.graphRef) return
+        const nodes = graphCtx.graphRef.current.nodes
+        const edges = graphCtx.graphRef.current.edges
         const newId = inputValue.trim()
         if (!newId || newId === nodeId) {
             setRenamingNodeId(null)
@@ -41,10 +43,10 @@ export function NodeHeaderTitle({ nodeId, displayTitle }: Props) {
             return
         }
         const { nodes: nextNodes, edges: nextEdges } = replaceNodeIdInGraph(nodes, edges, nodeId, newId)
-        setNodes(nextNodes)
+        setNodes(nextNodes as AppNode[])
         setEdges(nextEdges)
         setRenamingNodeId(null)
-    }, [nodeId, inputValue, nodes, edges, setNodes, setEdges, setRenamingNodeId])
+    }, [nodeId, inputValue, graphCtx?.graphRef, setNodes, setEdges, setRenamingNodeId])
 
     const cancelRename = useCallback(() => {
         setRenamingNodeId?.(null)

frontend/src/components/graph/NodeHelpPopover.tsx

@@ -0,0 +1,35 @@
+import React from 'react'
+import { HelpCircle } from 'lucide-react'
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover'
+import { getNodeHelp } from '@/lib/graph/nodeRegistry'
+import { cn } from '@/lib/utils'
+
+type Props = {
+    nodeType: string
+    className?: string
+}
+
+export function NodeHelpPopover({ nodeType, className }: Props) {
+    const { title, content } = getNodeHelp(nodeType)
+
+    return (
+        <Popover>
+            <PopoverTrigger
+                asChild
+                className={cn(
+                    'shrink-0 rounded p-0.5 text-muted-foreground hover:text-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring',
+                    className
+                )}
+                aria-label={`Help: ${title}`}
+            >
+                <button type="button">
+                    <HelpCircle className="size-3.5" />
+                </button>
+            </PopoverTrigger>
+            <PopoverContent side="top" align="end" className="w-80 max-h-[70vh] overflow-y-auto">
+                <h3 className="text-sm font-semibold text-foreground">{title}</h3>
+                <div className="mt-2">{content}</div>
+            </PopoverContent>
+        </Popover>
+    )
+}

frontend/src/components/graph/NodeMenubar.tsx

@@ -1,25 +1,27 @@
-import React, { useCallback, useContext } from 'react'
-import FlowContext from '../../lib/flowContext'
-import { DEFAULT_NODE_STYLE, getNextNodeId, getResetDataForType } from '../../lib/flowUtils'
+/**
+ * Per-node menubar (Node, Output, Data, Inputs, Insert). Content can be passed as props
+ * or resolved from the node type descriptor: when nodeMenuExtraContent is not provided,
+ * it is taken from getNodeType(nodeType)?.getNodeMenuExtraContent?.(nodeId, data).
+ */
+import React, { useCallback, useContext, useMemo } from 'react'
+import { GraphContext, FlowUIContext } from '@/lib/graph/flowContext'
+import { getNodeType } from '@/lib/graph/nodeRegistry'
 import {
     Menubar,
     MenubarContent,
     MenubarItem,
     MenubarMenu,
     MenubarSeparator,
+    MenubarShortcut,
     MenubarSub,
     MenubarSubContent,
     MenubarSubTrigger,
     MenubarTrigger,
-} from '../ui/menubar'
-
-const DUPLICATE_OFFSET = { x: 30, y: 30 }
-
-type NodeType = 'config' | 'render' | 'variable' | 'function'
-
+} from '@/components/ui/menubar'
+import { Kbd } from '@/components/ui/kbd'
 type Props = {
     nodeId: string
-    nodeType: NodeType
+    nodeType: string
     /** Content for Insert → Inputs (function nodes); when inputsMenuContent is set, Inputs is a separate menu and this is not used in Insert */
     editInputsContent?: React.ReactNode
     /** When set, Inputs is rendered as its own top-level menu (config nodes); Insert then only shows markup-specific options */
@@ -34,50 +36,27 @@ type Props = {
     insertTagsLabel?: string
     /** Extra content in Node menu (e.g. Export submenu for render nodes), before the separator */
     nodeMenuExtraContent?: React.ReactNode
+    /** When set, renders a top-level "Output" menu with this content (e.g. render node: preview/raw, viewport, export) */
+    outputMenuContent?: React.ReactNode
+    /** When set, renders a top-level "Data" menu with this content (e.g. data nodes) */
+    dataMenuContent?: React.ReactNode
 }
 
-export function NodeMenubar({ nodeId, nodeType, editInputsContent, inputsMenuContent, insertTagsContent, insertMenuLabel = 'Insert', insertContentDirect, insertTagsLabel = 'Tags', nodeMenuExtraContent }: Props) {
-    const ctx = useContext(FlowContext)
-    const nodes = ctx?.nodes ?? []
-    const setNodes = ctx?.setNodes
-    const setEdges = ctx?.setEdges
-
-    const edges = ctx?.edges ?? []
+export function NodeMenubar({ nodeId, nodeType, editInputsContent, inputsMenuContent, insertTagsContent, insertMenuLabel = 'Insert', insertContentDirect, insertTagsLabel = 'Tags', nodeMenuExtraContent: nodeMenuExtraContentProp, outputMenuContent, dataMenuContent }: Props) {
+    const graphCtx = useContext(GraphContext)
+    const uiCtx = useContext(FlowUIContext)
+    const nodes = graphCtx?.graphRef?.current?.nodes ?? []
+    const setNodes = graphCtx?.setNodes
+    const setEdges = graphCtx?.setEdges
+    const edges = graphCtx?.edges ?? []
     const node = nodes.find((n: any) => n.id === nodeId)
+    const nodeMenuExtraContent = useMemo(
+        () => nodeMenuExtraContentProp ?? getNodeType(nodeType)?.getNodeMenuExtraContent?.(nodeId, node?.data ?? {}),
+        [nodeMenuExtraContentProp, nodeType, nodeId, node?.data]
+    )
     const hasEdit = nodeType === 'config' || nodeType === 'function'
     const hasConnectedNodes = edges.some((e: any) => e.target === nodeId)
 
-    const onDuplicate = useCallback(() => {
-        if (!setNodes || !node) return
-        const pos = node.position ?? { x: 0, y: 0 }
-        setNodes((nds: any[]) => {
-            const newId = getNextNodeId(nodeType, nds.map((n: any) => n.id))
-            const newNode = {
-                id: newId,
-                type: node.type,
-                position: { x: pos.x + DUPLICATE_OFFSET.x, y: pos.y + DUPLICATE_OFFSET.y },
-                data: typeof node.data === 'object' && node.data !== null ? { ...node.data } : node.data,
-                style: DEFAULT_NODE_STYLE[nodeType] ?? DEFAULT_NODE_STYLE.config,
-            }
-            if (newNode.data?.title && nodeType === 'config') newNode.data.title = `${newId}`
-            return nds.concat(newNode)
-        })
-    }, [node, nodeType, setNodes])
-
-    const onCopy = useCallback(() => {
-        if (!node) return
-        const copy = { id: node.id, type: node.type, data: node.data, position: node.position, style: node.style }
-        navigator.clipboard?.writeText(JSON.stringify(copy)).catch(() => { })
-    }, [node])
-
-    const onReset = useCallback(() => {
-        if (!setNodes) return
-        const resetData = getResetDataForType(nodeType, nodeId)
-        setNodes((nds: any[]) =>
-            nds.map((n) => (n.id === nodeId ? { ...n, data: resetData } : n))
-        )
-    }, [nodeId, nodeType, setNodes])
-
     const onDelete = useCallback(() => {
         if (!setNodes || !setEdges) return
         setNodes((nds: any[]) => nds.filter((n: any) => n.id !== nodeId))
@@ -85,8 +64,8 @@ export function NodeMenubar({ nodeId, nodeType, editInputsContent, inputsMenuCon
     }, [nodeId, setNodes, setEdges])
 
     const onRename = useCallback(() => {
-        ctx?.setRenamingNodeId?.(nodeId)
-    }, [nodeId, ctx])
+        uiCtx?.setRenamingNodeId?.(nodeId)
+    }, [nodeId, uiCtx])
 
     return (
         <Menubar className="h-auto min-h-0 flex items-center bg-none p-1 border-t-0 border-l-0 border-r-0 border-b border-b-secondary shadow-none rounded-none text-muted-foreground">
@@ -94,26 +73,38 @@ export function NodeMenubar({ nodeId, nodeType, editInputsContent, inputsMenuCon
                 <MenubarTrigger className="px-1.5 py-0 text-xs">
                     Node
                 </MenubarTrigger>
-                <MenubarContent className="min-w-[10rem]">
-                    <MenubarItem className="text-xs" onClick={onDuplicate}>
-                        Duplicate
-                    </MenubarItem>
-                    <MenubarItem className="text-xs" onClick={onCopy}>
-                        Copy
-                    </MenubarItem>
+                <MenubarContent className="min-w-[12rem]">
                     <MenubarItem className="text-xs" onClick={onRename}>
                         Rename
                     </MenubarItem>
-                    <MenubarItem className="text-xs" onClick={onReset}>
-                        Reset
-                    </MenubarItem>
                     {nodeMenuExtraContent}
                     <MenubarSeparator />
                     <MenubarItem className="text-xs text-destructive focus:text-destructive" onClick={onDelete}>
                         Delete
+                        <MenubarShortcut className="ml-auto pl-4"><Kbd>⌫</Kbd></MenubarShortcut>
                     </MenubarItem>
                 </MenubarContent>
             </MenubarMenu>
+            {outputMenuContent != null && (
+                <MenubarMenu>
+                    <MenubarTrigger className="px-1.5 py-0 text-xs">
+                        Output
+                    </MenubarTrigger>
+                    <MenubarContent className="min-w-[12rem]">
+                        {outputMenuContent}
+                    </MenubarContent>
+                </MenubarMenu>
+            )}
+            {dataMenuContent != null && (
+                <MenubarMenu>
+                    <MenubarTrigger className="px-1.5 py-0 text-xs">
+                        Data
+                    </MenubarTrigger>
+                    <MenubarContent className="min-w-[12rem]">
+                        {dataMenuContent}
+                    </MenubarContent>
+                </MenubarMenu>
+            )}
             {inputsMenuContent != null && (
                 <MenubarMenu>
                     <MenubarTrigger className="px-1.5 py-0 text-xs" disabled={!hasConnectedNodes}>

frontend/src/components/graph/NodeStatusIndicator.tsx

@@ -1,6 +1,7 @@
 import { useId, useLayoutEffect, useRef, useState } from 'react'
 import type { ReactNode } from 'react'
 import { cn } from '@/lib/utils'
+import { observeResize } from '@/lib/sharedResizeObserver'
 
 export type NodeStatus = 'loading' | 'success' | 'error' | 'initial'
 
@@ -58,27 +59,15 @@ function BorderLoadingIndicator({
     useLayoutEffect(() => {
         const container = containerRef.current
         if (!container) return
-        // Observe the first child (BaseNode) so we use its actual rendered size.
         const target =
             container.firstElementChild instanceof HTMLElement
                 ? container.firstElementChild
                 : container
-        const syncMeasure = () => {
-            const cw = (target as HTMLElement).offsetWidth
-            const ch = (target as HTMLElement).offsetHeight
-            if (cw > 0 && ch > 0) {
-                queueMicrotask(() => setMeasured({ w: cw, h: ch }))
-            }
-        }
-        syncMeasure()
-        const ro = new ResizeObserver((entries) => {
-            const entry = entries[0]
-            if (!entry) return
-            const { width: cw, height: ch } = entry.contentRect
-            setMeasured({ w: Math.round(cw), h: Math.round(ch) })
+        // Use ResizeObserver only to avoid forced synchronous layout (offsetWidth/offsetHeight).
+        const unObserve = observeResize(target, ({ width: w, height: h }) => {
+            if (w > 0 && h > 0) setMeasured({ w, h })
         })
-        ro.observe(target)
-        return () => ro.disconnect()
+        return unObserve
     }, [])
 
     useLayoutEffect(() => {

frontend/src/components/nodes/agent/AgentNode.tsx

@@ -0,0 +1,152 @@
+import React, { useCallback, useContext, useMemo } from 'react'
+import {
+  AbstractNodeProps,
+  createAbstractNodeComponent,
+  useAbstractNode,
+} from '@/lib/graph/abstractNode'
+import {
+  BaseNode,
+  BaseNodeContent,
+  BaseNodeFooter,
+  BaseNodeHeaderRow,
+} from '@/components/graph/BaseNode'
+import { NodeMenubar } from '@/components/graph/NodeMenubar'
+import { NodeFooterEdgeIndicators } from '@/components/graph/NodeFooterEdgeIndicators'
+import { NodeHeaderTitle } from '@/components/graph/NodeHeaderTitle'
+import { InputHandle, OutputHandle } from '@/components/graph/NodeHandles'
+import { FlowUIContext } from '@/lib/graph/flowContext'
+import { useSyncConnectionStatus } from '@/lib/graph/nodeLifecycle'
+import { getNodeType } from '@/lib/graph/nodeRegistry'
+import { Bot } from 'lucide-react'
+import { Checkbox } from '@/components/ui/checkbox'
+
+export type AgentNodeData = {
+  /** Additional context for the agent (configuration). */
+  context?: string
+  /** When true, agent returns reasoning in a "## Reasoning" section and output in "## Output". */
+  reasoning?: boolean
+  /** Cached output from last run; set by connected Rendering node. Not displayed on this node. */
+  outputMarkdown?: string
+  /** Signature of inputs from last successful run; set by Rendering node when it runs the agent. Used as cache. */
+  lastRunSourceSignature?: string
+}
+
+type Props = AbstractNodeProps<AgentNodeData>
+
+function AgentNodeComponent({ id, data, width, height, selected }: Props) {
+  const flowUIContext = useContext(FlowUIContext)
+  const setFullscreenNodeId = flowUIContext?.setFullscreenNodeId
+  const supportsFullscreen = getNodeType('agent')?.supportsFullscreen
+  const { nodes, sourceIds, updateData } = useAbstractNode<AgentNodeData>(id, data ?? {})
+
+  const dimensions =
+    width != null && height != null && width > 0 && height > 0
+      ? { width, height }
+      : undefined
+
+  const contextText = data?.context ?? ''
+  const reasoningEnabled = data?.reasoning ?? false
+
+  const onReasoningChange = useCallback(
+    (checked: boolean) => updateData({ reasoning: checked }),
+    [updateData]
+  )
+
+  const connectedSources = useMemo(() => {
+    return sourceIds.map((sid) => {
+      const node = nodes.find((n: { id: string }) => n.id === sid)
+      return { id: sid, type: (node as { type?: string } | undefined)?.type ?? 'unknown' }
+    })
+  }, [sourceIds, nodes])
+
+  const onContextChange = useCallback(
+    (e: React.ChangeEvent<HTMLTextAreaElement>) => updateData({ context: e.target.value }),
+    [updateData]
+  )
+
+  // Agent is configuration-only; it does not block the flow. Only the Rendering node reports
+  // paused/updating, so the connection path runs trigger → … → agent (on-path) → rendering (paused).
+  useSyncConnectionStatus(id, {
+    updating: false,
+    error: false,
+    paused: false,
+  })
+
+  return (
+    <BaseNode
+      className="min-w-[360px] min-h-[320px]"
+      dimensions={dimensions}
+      resizable
+      nodeId={id}
+      selected={selected}
+      handles={
+        <>
+          <InputHandle id="in" nodeId={id} />
+          <OutputHandle id="out" />
+        </>
+      }
+    >
+      <BaseNodeHeaderRow
+        icon={<Bot className="size-4" />}
+        title={<NodeHeaderTitle nodeId={id} displayTitle={id} />}
+        onHeaderDoubleClick={supportsFullscreen && setFullscreenNodeId ? () => setFullscreenNodeId(id) : undefined}
+      />
+      <BaseNodeContent>
+        <div className="shrink-0 w-full">
+          <NodeMenubar nodeId={id} nodeType="agent" />
+        </div>
+        <div className="flex flex-col gap-3 p-2 min-h-0 flex-1">
+          <div className="flex flex-col gap-1.5">
+            <label htmlFor={`agent-reasoning-${id}`} className="flex items-center gap-2 text-xs font-medium text-foreground cursor-pointer">
+              <Checkbox
+                id={`agent-reasoning-${id}`}
+                checked={reasoningEnabled}
+                onCheckedChange={(c) => onReasoningChange(c === true)}
+                className="nodrag nopan"
+                aria-label="Enable reasoning"
+              />
+              Enable reasoning
+            </label>
+            <p className="text-xs text-muted-foreground">
+              When enabled, the model will output a Reasoning section and an Output section; the renderer shows them separately.
+            </p>
+          </div>
+          <div className="flex flex-col gap-1.5">
+            <label className="text-xs font-medium text-foreground">Context</label>
+            <textarea
+              className="nodrag nopan w-full min-h-[72px] rounded-md border border-input bg-background px-2 py-1.5 text-xs placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring"
+              placeholder="Additional context for the agent…"
+              value={contextText}
+              onChange={onContextChange}
+            />
+          </div>
+          <div className="flex flex-col gap-1.5">
+            <span className="text-xs font-medium text-foreground">Context from connected nodes</span>
+            {connectedSources.length === 0 ? (
+              <p className="text-xs text-muted-foreground">Connect Config, Variable, or Data nodes as input.</p>
+            ) : (
+              <ul className="text-xs text-muted-foreground list-disc list-inside space-y-0.5">
+                {connectedSources.map(({ id: sid, type }) => (
+                  <li key={sid}>
+                    <code className="rounded bg-muted px-1">{sid}</code> ({type})
+                  </li>
+                ))}
+              </ul>
+            )}
+          </div>
+          <p className="text-xs text-muted-foreground">
+            Connect to a Renderer node and click Run there to generate output.
+          </p>
+        </div>
+      </BaseNodeContent>
+      <BaseNodeFooter>
+        <NodeFooterEdgeIndicators nodeId={id} nodeType="agent">
+          —
+        </NodeFooterEdgeIndicators>
+      </BaseNodeFooter>
+    </BaseNode>
+  )
+}
+
+export const AgentNode = createAbstractNodeComponent<AgentNodeData>('AgentNode', AgentNodeComponent)
+export default AgentNode

frontend/src/components/nodes/agent/descriptor.tsx

@@ -0,0 +1,25 @@
+import React from 'react'
+import { Bot } from 'lucide-react'
+import { createNodeTypeBuilder } from '@/lib/graph/nodeTypeBuilder'
+import { NODE_HELP } from '@/lib/graph/nodeHelp'
+import type { NodeTypeDescriptor } from '@/lib/graph/nodeRegistry'
+import AgentNode from './AgentNode'
+import { agentRenderingLogic } from './renderingLogic'
+
+const ICON_CLASS = 'mr-2 h-4 w-4'
+
+export function getAgentNodeDescriptor(): NodeTypeDescriptor {
+  return createNodeTypeBuilder('agent', AgentNode, { width: 360, height: 320 }, { context: '' })
+    .idPrefix('agt_')
+    .withInputOutput(true, true)
+    .classification('archon')
+    .allowedSourceTypes(['config', 'variable', 'data', 'render'])
+    .allowedTargetTypes(['render'])
+    .help(NODE_HELP.agent)
+    .menu('Agent', <Bot className={ICON_CLASS} />)
+    .connectionLabelByStatus({ default: 'prompt/context', updating: 'running', paused: 'pending', error: 'corrupted' })
+    .withFullscreen()
+    .sourceRenderingLogic(agentRenderingLogic)
+    .outputMenuContent(() => null)
+    .build()
+}

frontend/src/components/nodes/agent/index.ts

@@ -0,0 +1,2 @@
+export { default as AgentNode, type AgentNodeData } from './AgentNode'
+export { getAgentNodeDescriptor } from './descriptor'

frontend/src/components/nodes/agent/renderingLogic.ts

@@ -0,0 +1,210 @@
+/**
+ * Agent node rendering logic: implements the "Resolve" step for agent sources.
+ * Calls the agent API and updates the agent node's output. Update mode is manual.
+ * See lib/graph/rendering.ts (IRenderingSource).
+ */
+
+import { getConfigContent } from '@/lib/graph/rendering'
+import type { ResolvedContentResult, SourceRenderingLogicContext } from '@/lib/graph/rendering'
+import type { AiConnection } from '@/app/kosmos/KosmosContext'
+
+function serializeNodeForContext(
+  nodes: { id: string; type?: string; data?: unknown }[],
+  nodeId: string
+): string {
+  const node = nodes.find((n) => n.id === nodeId)
+  if (!node) return `${nodeId}: (not found)`
+  const type = node.type ?? 'unknown'
+  const data = node.data as Record<string, unknown> | undefined
+  if (type === 'config') {
+    const content = getConfigContent(data)
+    return `[config ${nodeId}]\n${content || '(empty)'}`
+  }
+  if (type === 'variable') {
+    const v = data?.value
+    return `[variable ${nodeId}]: ${v === undefined || v === null ? '' : String(v)}`
+  }
+  if (type === 'data') {
+    const rows = (data?.rows as Record<string, string>[] | undefined) ?? []
+    const columns = (data?.columns as string[] | undefined) ?? []
+    const preview = rows
+      .slice(0, 20)
+      .map((r) => columns.map((c) => r[c] ?? '').join(', '))
+      .join('\n')
+    return `[data ${nodeId}] ${columns.length} columns, ${rows.length} rows\n${preview}${rows.length > 20 ? '\n...' : ''}`
+  }
+  return `[${type} ${nodeId}]: ${JSON.stringify(data ?? {}).slice(0, 200)}`
+}
+
+function buildSourceSignature(
+  nodes: { id: string; type?: string; data?: unknown }[],
+  sourceIds: string[]
+): string {
+  const configContents = sourceIds
+    .filter((sid) => {
+      const n = nodes.find((nn) => nn.id === sid)
+      return (n as { type?: string } | undefined)?.type === 'config'
+    })
+    .map((sid) =>
+      getConfigContent(
+        (nodes.find((n) => n.id === sid)?.data ?? undefined) as Record<string, unknown> | undefined
+      )
+    )
+  return JSON.stringify({ sourceIds: sourceIds.slice().sort(), configContents })
+}
+
+/** Parse agent response into reasoning and output when format is "## Reasoning" / "## Output". */
+function parseReasoningAndOutput(fullMarkdown: string): { reasoning?: string; output: string } {
+  const normalized = fullMarkdown.trim()
+  const outputMatch = normalized.match(/\s*##\s*Output\s*/i)
+  if (!outputMatch) return { output: fullMarkdown }
+  const idx = outputMatch.index! + outputMatch[0].length
+  const output = normalized.slice(idx).trim()
+  const beforeOutput = normalized.slice(0, outputMatch.index).trim()
+  const reasoningMatch = beforeOutput.match(/\s*##\s*Reasoning\s*/i)
+  const reasoning = reasoningMatch
+    ? beforeOutput.slice(reasoningMatch.index! + reasoningMatch[0].length).trim()
+    : beforeOutput
+  return { reasoning: reasoning || undefined, output: output || fullMarkdown }
+}
+
+export const agentRenderingLogic = {
+  defaultUpdateMode: 'manual' as const,
+  getResolvedContent: async (context: SourceRenderingLogicContext): Promise<ResolvedContentResult> => {
+    const { nodes, sourceNodeId, setNodes, aiConnection, onStreamingStart, onStreamingChunk } = context
+    const sourceNode = nodes.find((n) => n.id === sourceNodeId)
+    const agentData = sourceNode?.data as { context?: string; outputMarkdown?: string; reasoning?: boolean } | undefined
+    const contextText = agentData?.context ?? ''
+    const reasoningEnabled = Boolean(agentData?.reasoning)
+    const sourceIds = (context.edges
+      .filter((e) => e.target === sourceNodeId)
+      .map((e) => e.source)) as string[]
+
+    type NodeWithData = { id: string; type?: string; data?: unknown }
+    const setAgentData = (patch: Record<string, unknown>) => {
+      if (!setNodes) return
+      setNodes((prev: unknown[]) =>
+        (prev as NodeWithData[]).map((n) =>
+          n.id === sourceNodeId ? { ...n, data: { ...(n.data as object), ...patch } } : n
+        )
+      )
+    }
+
+    if (setNodes && aiConnection) {
+      const connection = aiConnection as AiConnection
+      const configContents = sourceIds
+        .filter((sid) => {
+          const n = nodes.find((nn) => nn.id === sid)
+          return (n as { type?: string } | undefined)?.type === 'config'
+        })
+        .map((sid) =>
+          getConfigContent(
+            (nodes.find((n) => n.id === sid)?.data ?? undefined) as Record<string, unknown> | undefined
+          )
+        )
+      const prompt =
+        configContents.length > 0
+          ? configContents.join('\n\n---\n\n')
+          : 'No prompt provided. Please describe what you want in structured markdown.'
+      const contextNodes = sourceIds.map((sid) => ({
+        id: sid,
+        content: serializeNodeForContext(nodes, sid),
+      }))
+      const sourceSignature = buildSourceSignature(nodes, sourceIds)
+      const useStream = Boolean(onStreamingChunk)
+
+      try {
+        if (useStream) {
+          onStreamingStart?.()
+          const res = await fetch('/api/agent/stream', {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({
+              prompt,
+              context: contextText.trim() || undefined,
+              contextNodes,
+              connection,
+              reasoning: reasoningEnabled,
+            }),
+          })
+          if (!res.ok) {
+            const text = await res.text().catch(() => '')
+            let msg = `Request failed: ${res.status}`
+            try {
+              const json = text ? JSON.parse(text) : {}
+              if (typeof (json as { error?: string }).error === 'string') msg = (json as { error: string }).error
+            } catch {
+              if (text) msg = text.slice(0, 200)
+            }
+            setAgentData({ outputMarkdown: undefined })
+            throw new Error(msg)
+          }
+          const reader = res.body?.getReader()
+          const decoder = new TextDecoder()
+          let markdown = ''
+          try {
+            if (reader) {
+              while (true) {
+                const { done, value } = await reader.read()
+                if (done) break
+                const chunk = decoder.decode(value, { stream: true })
+                markdown += chunk
+                onStreamingChunk?.(chunk)
+              }
+            }
+          } finally {
+            reader?.cancel()
+          }
+          setAgentData({
+            outputMarkdown: markdown,
+            lastRunSourceSignature: sourceSignature,
+          })
+          if (reasoningEnabled) {
+            const { reasoning: reasoningText, output } = parseReasoningAndOutput(markdown)
+            return { resolved: output, outputTypeId: 'markdown' as const, reasoning: reasoningText }
+          }
+          return { resolved: markdown, outputTypeId: 'markdown' }
+        }
+
+        const res = await fetch('/api/agent', {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({
+            prompt,
+            context: contextText.trim() || undefined,
+            contextNodes,
+            connection,
+            reasoning: reasoningEnabled,
+          }),
+        })
+        const json = await res.json().catch(() => ({}))
+        if (!res.ok) {
+          setAgentData({ outputMarkdown: undefined })
+          const msg = (json as { error?: string }).error ?? `Request failed: ${res.status}`
+          throw new Error(msg)
+        }
+        const markdown = (json as { markdown?: string }).markdown ?? ''
+        setAgentData({
+          outputMarkdown: markdown,
+          lastRunSourceSignature: sourceSignature,
+        })
+        if (reasoningEnabled) {
+          const { reasoning: reasoningText, output } = parseReasoningAndOutput(markdown)
+          return { resolved: output, outputTypeId: 'markdown' as const, reasoning: reasoningText }
+        }
+        return { resolved: markdown, outputTypeId: 'markdown' }
+      } catch (err: unknown) {
+        setAgentData({ outputMarkdown: undefined })
+        throw err instanceof Error ? err : new Error('Agent request failed')
+      }
+    }
+
+    const outputMarkdown =
+      (sourceNode?.data as { outputMarkdown?: string } | undefined)?.outputMarkdown ?? ''
+    if (reasoningEnabled && outputMarkdown) {
+      const { reasoning: reasoningText, output } = parseReasoningAndOutput(outputMarkdown)
+      return { resolved: output, outputTypeId: 'markdown' as const, reasoning: reasoningText }
+    }
+    return { resolved: outputMarkdown, outputTypeId: 'markdown' }
+  },
+}

frontend/src/components/nodes/config/ConfigNode.tsx

@@ -1,29 +1,31 @@
-import React, { memo, useCallback, useContext, useMemo, useRef } from 'react'
-import { autocompletion } from '@codemirror/autocomplete'
-import CodeMirror from '@uiw/react-codemirror'
-import { javascript } from '@codemirror/lang-javascript'
-import { markdown } from '@codemirror/lang-markdown'
-import FlowContext from '../../lib/flowContext'
-import { nodePropsAreEqual } from '../../lib/flowUtils'
-import { useResizeHeight } from '../../hooks/useResizeHeight'
-import { nunjucksCompletionSource } from '../../lib/nunjucksAutocomplete'
-import { plantumlLanguage } from '../../lib/plantumlLanguage'
-import { useTheme } from '../../lib/themeContext'
+import React, { useCallback, useContext, useId, useMemo } from 'react'
 import {
-    CONFIG_TYPES,
+    AbstractNodeProps,
+    createAbstractNodeComponent,
+    getConnectedNodesByType,
+    useAbstractNode,
+} from '@/lib/graph/abstractNode'
+import { CodeEditor } from '@/components/editor/CodeEditor'
+import { useSimpleEditorInsert } from '@/hooks/useSimpleEditorInsert'
+import { useResizeHeight } from '@/hooks/useResizeHeight'
+import { type HighlightLanguage } from '@/lib/syntaxHighlight'
+import {
+    getConfigTypes,
     getConfigContent,
     getConfigType,
     getConfigTypeId,
     isGroup,
     type ConfigTypeId,
-} from '../../lib/configTypes'
+    type InsertBlockGroup,
+    type InsertBlock,
+} from '@/lib/graph/configTypes'
 import {
     BaseNode,
     BaseNodeContent,
     BaseNodeFooter,
     BaseNodeHeaderRow,
-} from './BaseNode'
-import { Code2, ScrollText, Variable } from 'lucide-react'
+} from '@/components/graph/BaseNode'
+import { Code2, Database, ScrollText, Sparkles, Variable } from 'lucide-react'
 import {
     MenubarItem,
     MenubarSeparator,
@@ -31,111 +33,72 @@ import {
     MenubarSub,
     MenubarSubContent,
     MenubarSubTrigger,
-} from '../ui/menubar'
-import { Kbd } from '../ui/kbd'
-import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '../ui/select'
-import { InputHandle, OutputHandle } from './NodeHandles'
-import { NodeFooterEdgeIndicators } from './NodeFooterEdgeIndicators'
-import { NodeHeaderTitle } from './NodeHeaderTitle'
-import { NodeMenubar } from './NodeMenubar'
+} from '@/components/ui/menubar'
+import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
+import { Kbd } from '@/components/ui/kbd'
+import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select'
+import { InputHandle, OutputHandle } from '@/components/graph/NodeHandles'
+import { NodeFooterEdgeIndicators } from '@/components/graph/NodeFooterEdgeIndicators'
+import { NodeHeaderTitle } from '@/components/graph/NodeHeaderTitle'
+import { NodeMenubar } from '@/components/graph/NodeMenubar'
+import { FlowUIContext } from '@/lib/graph/flowContext'
+import { getNodeType } from '@/lib/graph/nodeRegistry'
 
-type Props = {
-    id: string
-    data: any
-    width?: number
-    height?: number
-}
+export type ConfigNodeData = { configType?: ConfigTypeId; content?: string; title?: string; /** @deprecated use content */ plantuml?: string }
 
-export const ConfigNode = memo(function ConfigNode({ id, data, width, height }: Props) {
-    const configTypeId = getConfigTypeId(data)
+type Props = AbstractNodeProps<ConfigNodeData>
+
+function ConfigNodeComponent({ id, data, width, height, selected }: Props) {
+    const flowUIContext = useContext(FlowUIContext)
+    const setFullscreenNodeId = flowUIContext?.setFullscreenNodeId
+    const supportsFullscreen = getNodeType('config')?.supportsFullscreen
+    const configTypeId = getConfigTypeId(data ?? {})
     const configType = getConfigType(configTypeId)
-    const content = getConfigContent(data)
-    const { theme } = useTheme()
-    const ctx = useContext(FlowContext)
-    const setNodes = ctx?.setNodes
+    const content = getConfigContent(data ?? {})
+    const { nodes, sourceIds, updateData } = useAbstractNode<ConfigNodeData>(id, data ?? {})
+    const editorId = useId()
+    const onChange = useCallback(
+        (val: string) => updateData({ content: val, configType: configTypeId }),
+        [updateData, configTypeId]
+    )
+    const insertAt = useSimpleEditorInsert(editorId, content, onChange)
 
-    const editorRef = useRef<unknown>(null)
-
-    const edges = ctx?.edges ?? []
-    const nodes = ctx?.nodes ?? []
-    const incomingEdges = useMemo(() => edges.filter((e: any) => e.target === id), [edges, id])
-    const incomingIds = useMemo(() => incomingEdges.map((e: any) => e.source).sort(), [incomingEdges])
     const connectedConfigNodes = useMemo(
-        () => (nodes as any[]).filter((n: any) => incomingIds.includes(n.id) && n.type === 'config'),
-        [nodes, incomingIds]
+        () => getConnectedNodesByType(nodes, sourceIds, 'config'),
+        [nodes, sourceIds]
     )
     const connectedVariableNodes = useMemo(
-        () => (nodes as any[]).filter((n: any) => incomingIds.includes(n.id) && n.type === 'variable'),
-        [nodes, incomingIds]
+        () => getConnectedNodesByType(nodes, sourceIds, 'variable'),
+        [nodes, sourceIds]
     )
     const connectedFunctionNodes = useMemo(
-        () => (nodes as any[]).filter((n: any) => incomingIds.includes(n.id) && n.type === 'function'),
-        [nodes, incomingIds]
+        () => getConnectedNodesByType(nodes, sourceIds, 'function'),
+        [nodes, sourceIds]
     )
-    const hasDependencies = connectedConfigNodes.length > 0 || connectedVariableNodes.length > 0 || connectedFunctionNodes.length > 0
-
-    const onChange = useCallback(
-        (val: string) => {
-            if (setNodes) {
-                setNodes((nds: any[]) =>
-                    nds.map((n) =>
-                        n.id === id ? { ...n, data: { ...n.data, content: val, configType: configTypeId } } : n
-                    )
-                )
-            }
-        },
-        [id, setNodes, configTypeId]
+    const connectedDataNodes = useMemo(
+        () => getConnectedNodesByType(nodes, sourceIds, 'data'),
+        [nodes, sourceIds]
     )
+    const connectedRenderNodes = useMemo(
+        () => getConnectedNodesByType(nodes, sourceIds, 'render'),
+        [nodes, sourceIds]
+    )
+    const hasDependencies =
+        connectedConfigNodes.length > 0 ||
+        connectedVariableNodes.length > 0 ||
+        connectedFunctionNodes.length > 0 ||
+        connectedDataNodes.length > 0 ||
+        connectedRenderNodes.length > 0
 
     const setConfigType = useCallback(
         (newTypeId: ConfigTypeId) => {
-            if (!setNodes || newTypeId === configTypeId) return
-            setNodes((nds: any[]) =>
-                nds.map((n) =>
-                    n.id === id
-                        ? {
-                              ...n,
-                              data: {
-                                  ...n.data,
-                                  configType: newTypeId,
-                                  content: getConfigContent(n.data) ?? '',
-                              },
-                          }
-                        : n
-                )
-            )
+            if (newTypeId === configTypeId) return
+            updateData({
+                configType: newTypeId,
+                content: getConfigContent({ ...data, configType: newTypeId }) ?? '',
+            })
         },
-        [id, setNodes, configTypeId]
-    )
-
-    const insertAt = useCallback(
-        (insertText: string, mode: 'prepend' | 'append' | 'cursor') => {
-            const ref = editorRef.current as { view: { state: { doc: { length: number; toString(): string }; selection: { main: { from: number } } }; dispatch: (arg: { changes: { from: number; to: number; insert: string } }) => void } } | null
-            if (ref?.view) {
-                const view = ref.view
-                const doc = view.state.doc
-                const len = doc.length
-                let from: number
-                if (mode === 'prepend') {
-                    from = 0
-                } else if (mode === 'append') {
-                    from = len
-                } else {
-                    const main = view.state.selection.main
-                    from = main.from
-                }
-                view.dispatch({ changes: { from, to: from, insert: insertText } })
-                const newVal = view.state.doc.toString()
-                onChange(newVal)
-                return
-            }
-            if (mode === 'prepend') {
-                onChange(insertText + content)
-            } else {
-                onChange(content + insertText)
-            }
-        },
-        [onChange, content]
+        [configTypeId, data, updateData]
     )
 
     const insertExtendsFromNode = useCallback(
@@ -173,60 +136,67 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
         [insertAt]
     )
 
+    const insertDataReference = useCallback(
+        (sourceNode: any, mode: 'prepend' | 'append' | 'cursor') => {
+            insertAt(`{% for row in ${sourceNode.id} %}\n  \n{% endfor %}`, mode)
+        },
+        [insertAt]
+    )
+
+    const insertRenderReference = useCallback(
+        (sourceNode: any, mode: 'prepend' | 'append' | 'cursor') => {
+            const isMarkdownImage =
+                configTypeId === 'markdown' && (sourceNode.data?.outputMode ?? 'image') === 'image'
+            const snippet = isMarkdownImage
+                ? `![Rendered]({{ ${sourceNode.id} }})`
+                : `{{ ${sourceNode.id} }}`
+            insertAt(snippet, mode)
+        },
+        [insertAt, configTypeId]
+    )
+
     const variableIds = useMemo(() => connectedVariableNodes.map((n: any) => n.id), [connectedVariableNodes])
     const functionIds = useMemo(() => connectedFunctionNodes.map((n: any) => n.id), [connectedFunctionNodes])
     const configTitles = useMemo(
         () => connectedConfigNodes.map((n: any) => n.data?.title ?? n.id),
         [connectedConfigNodes],
     )
-    const extensions = useMemo(() => {
-        const lang =
-            configTypeId === 'wireframe'
-                ? javascript()
-                : configType.language === 'plantuml'
-                  ? plantumlLanguage.extension
-                  : markdown()
-        return [
-            lang,
-            autocompletion({
-                override: [nunjucksCompletionSource(variableIds, configTitles, functionIds)],
-                activateOnTyping: true,
-            }),
-        ]
-    }, [configTypeId, configType.language, variableIds, functionIds, configTitles])
+    const dataIds = useMemo(() => connectedDataNodes.map((n: any) => n.id), [connectedDataNodes])
+    const highlightLang: HighlightLanguage =
+        configTypeId === 'wireframe' ? 'javascript' : configType.language === 'plantuml' ? 'plantuml' : 'markdown'
     const [editorHeight, editorContainerRef] = useResizeHeight(180)
 
     const insertBlocksContent = useMemo(() => {
         const templatingGroup = configType.insertBlocks.find(
-            (b): b is import('../../lib/configTypes').InsertBlockGroup => isGroup(b) && b.label === 'Templating'
+            (b): b is InsertBlockGroup => isGroup(b) && b.label === 'Templating'
         )
         const typeBlocks = configType.insertBlocks.filter((b) => !(isGroup(b) && b.label === 'Templating'))
         const insertShortcut = <MenubarShortcut className="opacity-0 group-hover:opacity-100 transition-opacity"><Kbd>Insert</Kbd></MenubarShortcut>
         const typeItems = typeBlocks.flatMap((block) =>
             isGroup(block)
-                ? block.items.map(({ label, snippet }) => (
-                      <MenubarItem
-                          key={label}
-                          className="text-xs flex items-center group"
-                          onClick={() => insertAt(snippet, 'cursor')}
-                      >
-                          {label}
-                          {insertShortcut}
-                      </MenubarItem>
-                  ))
+                ? block.items.map(({ label, snippet }: InsertBlock) => (
+                    <MenubarItem
+                        key={label}
+                        className="text-xs flex items-center group"
+                        onClick={() => insertAt(snippet, 'cursor')}
+                    >
+                        {label}
+                        {insertShortcut}
+                    </MenubarItem>
+                ))
                 : [
-                      <MenubarItem
-                          key={block.label}
-                          className="text-xs flex items-center group"
-                          onClick={() => insertAt(block.snippet, 'cursor')}
-                      >
-                          {block.label}
-                          {insertShortcut}
-                      </MenubarItem>,
-                  ]
+                    <MenubarItem
+                        key={block.label}
+                        className="text-xs flex items-center group"
+                        onClick={() => insertAt(block.snippet, 'cursor')}
+                    >
+                        {block.label}
+                        {insertShortcut}
+                    </MenubarItem>,
+                ]
         )
         const templatingItems =
-            templatingGroup?.items.map(({ label, snippet }) => (
+            templatingGroup?.items.map(({ label, snippet }: InsertBlock) => (
                 <MenubarItem
                     key={label}
                     className="text-xs flex items-center group"
@@ -255,7 +225,7 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
             : undefined
 
     return (
-        <BaseNode className="min-w-80 min-h-[280px]" dimensions={dimensions} resizable nodeId={id} handles={<><InputHandle id="ain" nodeId={id} /><OutputHandle id="out" /></>}>
+        <BaseNode className="min-w-80 min-h-[280px]" dimensions={dimensions} resizable nodeId={id} selected={selected} handles={<><InputHandle id="ain" nodeId={id} /><OutputHandle id="out" /></>}>
             <BaseNodeHeaderRow
                 icon={<ScrollText className="size-4" />}
                 title={<NodeHeaderTitle nodeId={id} displayTitle={`${id}`} />}
@@ -265,7 +235,7 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
                             <SelectValue />
                         </SelectTrigger>
                         <SelectContent>
-                            {CONFIG_TYPES.map((t) => (
+                            {getConfigTypes().map((t) => (
                                 <SelectItem key={t.id} value={t.id} className="text-xs">
                                     {t.label}
                                 </SelectItem>
@@ -273,6 +243,7 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
                         </SelectContent>
                     </Select>
                 }
+                onHeaderDoubleClick={supportsFullscreen && setFullscreenNodeId ? () => setFullscreenNodeId(id) : undefined}
             />
 
             <BaseNodeContent>
@@ -336,6 +307,51 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
                                             <MenubarShortcut className="opacity-0 group-hover:opacity-100 transition-opacity"><Kbd>Insert</Kbd></MenubarShortcut>
                                         </MenubarItem>
                                     ))}
+                                    {connectedDataNodes.map((n: any) => (
+                                        <MenubarItem
+                                            key={n.id}
+                                            className="text-xs flex items-center gap-2 group"
+                                            onClick={() => insertDataReference(n, 'cursor')}
+                                        >
+                                            <Database className="size-3.5 shrink-0" />
+                                            {n.id}
+                                            <MenubarShortcut className="opacity-0 group-hover:opacity-100 transition-opacity"><Kbd>Insert</Kbd></MenubarShortcut>
+                                        </MenubarItem>
+                                    ))}
+                                    {connectedRenderNodes.map((n: any) => {
+                                        const renderInputDisabled =
+                                            configTypeId === 'plantuml' || configTypeId === 'wireframe'
+                                        const item = (
+                                            <MenubarItem
+                                                key={n.id}
+                                                className="text-xs flex items-center gap-2 group"
+                                                disabled={renderInputDisabled}
+                                                onClick={() =>
+                                                    !renderInputDisabled && insertRenderReference(n, 'cursor')
+                                                }
+                                            >
+                                                <Sparkles className="size-3.5 shrink-0" />
+                                                {n.id}
+                                                <MenubarShortcut className="opacity-0 group-hover:opacity-100 transition-opacity">
+                                                    <Kbd>Insert</Kbd>
+                                                </MenubarShortcut>
+                                            </MenubarItem>
+                                        )
+                                        return renderInputDisabled ? (
+                                            <TooltipProvider key={n.id} delayDuration={300}>
+                                                <Tooltip>
+                                                    <TooltipTrigger asChild>{item}</TooltipTrigger>
+                                                    <TooltipContent side="right">
+                                                        Rendering output is not available for Diagram and
+                                                        Wireframe configs. Use a Markdown config to embed
+                                                        render output.
+                                                    </TooltipContent>
+                                                </Tooltip>
+                                            </TooltipProvider>
+                                        ) : (
+                                            item
+                                        )
+                                    })}
                                 </>
                             ) : (
                                 <span className="text-xs text-muted-foreground px-2 py-1">Connect nodes to insert references</span>
@@ -347,17 +363,17 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
                     />
                 </div>
 
-                <div ref={editorContainerRef} className="min-h-0 flex-1 w-full nodrag nopan overflow-hidden border-t border-input">
-                    <CodeMirror
-                        // @ts-expect-error ref is { view, state, editor }; package ref type not in our node_modules
-                        ref={editorRef}
+                <div ref={editorContainerRef as React.RefObject<HTMLDivElement>} className="min-h-0 flex-1 w-full nodrag nopan overflow-hidden border-t border-input" style={{ minHeight: editorHeight }}>
+                    <CodeEditor
+                        textareaId={editorId}
                         value={content}
-                        height={`${editorHeight}px`}
-                        theme={theme}
-                        extensions={extensions}
-                        onChange={onChange}
-                        basicSetup={{ lineNumbers: true, foldGutter: false }}
-                        className="text-sm [&_.cm-editor]:outline-none [&_.cm-editor]:cursor-text [&_.cm-gutters]:border-0"
+                        onValueChange={onChange}
+                        language={highlightLang}
+                        minHeight={editorHeight}
+                        style={{ fontSize: 14 }}
+                        textareaClassName="text-sm outline-none border-0 resize-none nodrag nopan"
+                        preClassName="text-sm nodrag nopan"
+                        className="min-h-0 w-full"
                     />
                 </div>
             </BaseNodeContent>
@@ -369,8 +385,11 @@ export const ConfigNode = memo(function ConfigNode({ id, data, width, height }:
             </BaseNodeFooter>
         </BaseNode>
     )
-}, nodePropsAreEqual)
+}
 
-ConfigNode.displayName = 'ConfigNode'
+export const ConfigNode = createAbstractNodeComponent<ConfigNodeData>(
+    'ConfigNode',
+    ConfigNodeComponent
+)
 
 export default ConfigNode

frontend/src/components/nodes/config/descriptor.tsx

@@ -0,0 +1,93 @@
+import React from 'react'
+import { ScrollText } from 'lucide-react'
+import { createNodeTypeBuilder } from '@/lib/graph/nodeTypeBuilder'
+import { NODE_HELP } from '@/lib/graph/nodeHelp'
+import { getConfigType } from '@/lib/graph/rendering'
+import {
+  MenubarItem,
+  MenubarSeparator,
+  MenubarSub,
+  MenubarSubContent,
+  MenubarSubTrigger,
+} from '@/components/ui/menubar'
+import { getResolvedContentForConfig } from './renderingLogic'
+import type { NodeTypeDescriptor } from '@/lib/graph/nodeRegistry'
+import ConfigNode from './ConfigNode'
+import { createImageExportHandlers, type OutputMenuContext } from '@/components/nodes/render/outputMenuHandlers'
+
+const ICON_CLASS = 'mr-2 h-4 w-4'
+
+function configOutputMenuContent(outputTypeId: string, ctx: unknown): React.ReactNode {
+  const c = ctx as OutputMenuContext
+  const configType = getConfigType(outputTypeId as 'plantuml' | 'markdown' | 'wireframe')
+  const descriptor = configType?.outputMenuDescriptor
+  if (!descriptor?.items?.length) return null
+  const disabled = !c.state.isSvgOutput
+  const handlers = createImageExportHandlers(c)
+  return (
+    <>
+      <MenubarSeparator />
+      <MenubarSub>
+        <MenubarSubTrigger className="text-xs" disabled={disabled}>
+          {descriptor.submenuLabel ?? 'Export'}
+        </MenubarSubTrigger>
+        <MenubarSubContent className="min-w-[10rem]" aria-label={descriptor.submenuLabel ?? 'Export'}>
+          {descriptor.items.map((item) => {
+            const handler =
+              item.action === 'downloadSvg'
+                ? handlers.downloadSvg
+                : item.action === 'downloadPng'
+                  ? handlers.downloadPng
+                  : item.action === 'copySvg'
+                    ? handlers.copySvg
+                    : handlers.copyPng
+            return (
+              <MenubarItem
+                key={item.id}
+                className="text-xs"
+                onClick={handler}
+                disabled={disabled}
+              >
+                {item.label}
+              </MenubarItem>
+            )
+          })}
+        </MenubarSubContent>
+      </MenubarSub>
+    </>
+  )
+}
+
+export function getConfigNodeDescriptor(): NodeTypeDescriptor {
+  return createNodeTypeBuilder(
+    'config',
+    ConfigNode,
+    { width: 320, height: 320 },
+    { configType: 'plantuml', content: '@startuml\n\n@enduml\n', title: '' }
+  )
+    .idPrefix('cfg_')
+    .withInputOutput(true, true)
+    .classification('psyche')
+    .allowedSourceTypes(['config', 'variable', 'function', 'data', 'render'])
+    .allowedTargetTypes(['config', 'render', 'agent'])
+    .help(NODE_HELP.config)
+    .menu('Config', <ScrollText className={ICON_CLASS} />)
+    .getDefaultData((newId) => ({
+      configType: 'plantuml',
+      content: '@startuml\n\n@enduml\n',
+      title: newId ?? '',
+    }))
+    .getResetData((nodeId) => ({
+      configType: 'plantuml',
+      content: '@startuml\n\n@enduml\n',
+      title: nodeId ?? '',
+    }))
+    .connectionLabelByStatus({ default: 'adding input', updating: 'pushing new form', paused: 'pending', error: 'corrupted' })
+    .withFullscreen()
+    .sourceRenderingLogic({
+      defaultUpdateMode: 'auto',
+      getResolvedContent: getResolvedContentForConfig,
+    })
+    .outputMenuContent(configOutputMenuContent)
+    .build()
+}

frontend/src/components/nodes/config/index.ts

@@ -0,0 +1,2 @@
+export { default as ConfigNode, type ConfigNodeData } from './ConfigNode'
+export { getConfigNodeDescriptor } from './descriptor'

frontend/src/components/nodes/config/renderingLogic.ts

@@ -0,0 +1,285 @@
+/**
+ * Config node rendering logic: implements the "Resolve" step for config sources.
+ * Resolves Nunjucks (extends/include/import, variables, data, functions) and returns
+ * resolved string + output type. See lib/graph/rendering.ts (IRenderingSource).
+ */
+
+import nunjucks from 'nunjucks'
+import type { ResolvedContentResult, SourceRenderingLogicContext } from '@/lib/graph/rendering'
+import { getConfigContent, getConfigType, getConfigTypeId, type ConfigTypeId } from '@/lib/graph/rendering'
+import { isReachable, resolveExtendsRef, getTemplateRefs, type NodeLike } from '@/lib/graph/templateRefs'
+
+// Module-level cache for resolved Nunjucks output.
+// Keyed by a fingerprint of all inputs (template contents + variable/data values + function bodies).
+// Avoids re-running the Nunjucks environment when the same inputs are seen again (e.g. undo/redo,
+// multiple rendering nodes sharing the same config, rapid edits cycling back to a prior value).
+const MAX_RESOLVE_CACHE = 200
+const resolveCache = new Map<string, ResolvedContentResult>()
+
+export async function getResolvedContentForConfig(context: SourceRenderingLogicContext): Promise<ResolvedContentResult> {
+  const { nodes, edges, sourceNodeId, renderNodeId } = context
+  const srcId = sourceNodeId
+  const id = renderNodeId
+  const sourceNode = nodes.find((n) => n.id === sourceNodeId)
+  const outputTypeId: ConfigTypeId = sourceNode
+    ? getConfigTypeId((sourceNode.data ?? undefined) as Record<string, unknown> | undefined)
+    : 'plantuml'
+
+  const configIdsUsed = new Set<string>()
+
+  const addConfigAndRefs = (templateName: string, visited = new Set<string>()) => {
+    const refId = resolveExtendsRef(nodes, templateName)
+    if (visited.has(refId)) throw new Error(`Circular reference detected: ${templateName}`)
+    const node = nodes.find((n) => n.id === refId && n.type === 'config')
+    if (!node) throw new Error(`Config not found: ${templateName}`)
+    if (refId !== srcId && !isReachable(edges, refId, id))
+      throw new Error(`Referenced config not connected to renderer: ${templateName}`)
+    visited.add(refId)
+    configIdsUsed.add(refId)
+    const content = getConfigContent((node.data ?? undefined) as Record<string, unknown> | undefined)
+    for (const ref of getTemplateRefs(content)) addConfigAndRefs(ref, visited)
+  }
+
+  addConfigAndRefs(srcId)
+
+  const configLoader = {
+    getSource: (name: string): { src: string; path: string } | null => {
+      const refId = resolveExtendsRef(nodes, name)
+      const node = nodes.find((n) => n.id === refId && n.type === 'config')
+      if (!node) return null
+      if (refId !== srcId && !isReachable(edges, refId, id))
+        throw new Error(`Referenced config not connected to renderer: ${name}`)
+      return {
+        src: getConfigContent((node.data ?? undefined) as Record<string, unknown> | undefined),
+        path: name,
+      }
+    },
+  }
+
+  const nunjucksContext = Object.create(null) as Record<string, unknown>
+  const setVarInContext = (src: NodeLike) => {
+    const v = (src.data as Record<string, unknown>)?.value
+    const str = v === undefined || v === null ? '' : String(v)
+    nunjucksContext[src.id] =
+      v === undefined || v === null ? '' : typeof v === 'boolean' || typeof v === 'number' ? v : str
+  }
+  for (const e of edges) {
+    if (!configIdsUsed.has(e.target)) continue
+    const src = nodes.find((n) => n.id === e.source)
+    if (src?.type === 'variable') setVarInContext(src)
+    if (src?.type === 'data') {
+      const rows = ((src.data as Record<string, unknown>)?.rows as Record<string, string>[]) ?? []
+      const hidden = ((src.data as Record<string, unknown>)?.hiddenColumns as string[]) ?? []
+      const visibleCols = ((src.data as Record<string, unknown>)?.columns as string[] | undefined) ?? []
+      const filtered = (visibleCols as string[]).filter((c) => !hidden.includes(c))
+      const filteredRows = rows.map((row) => {
+        const out: Record<string, string> = {}
+        for (const col of filtered) {
+          if (col in row) out[col] = row[col]
+        }
+        return out
+      })
+      nunjucksContext[src.id] = filteredRows
+    }
+    if (src?.type === 'render') {
+      nunjucksContext[src.id] =
+        ((src.data as Record<string, unknown>)?.cachedOutputValue as string | undefined) ?? ''
+    }
+  }
+
+  const functionIdsToRegister = new Set<string>()
+  let added = true
+  while (added) {
+    added = false
+    for (const e of edges) {
+      const src = nodes.find((n) => n.id === e.source)
+      if (src?.type !== 'function') continue
+      const targetInScope = configIdsUsed.has(e.target) || functionIdsToRegister.has(e.target)
+      if (!targetInScope) continue
+      if (!functionIdsToRegister.has(src.id)) {
+        functionIdsToRegister.add(src.id)
+        added = true
+      }
+    }
+  }
+  for (const e of edges) {
+    if (!configIdsUsed.has(e.target) && !functionIdsToRegister.has(e.target)) continue
+    const src = nodes.find((n) => n.id === e.source)
+    if (src?.type === 'function') {
+      for (const e2 of edges) {
+        if (e2.target !== src.id) continue
+        const vNode = nodes.find((n) => n.id === e2.source)
+        if (vNode?.type === 'variable') setVarInContext(vNode)
+      }
+    }
+  }
+
+  // Build cache key from all inputs that affect the resolved output.
+  const allTemplateContents = [...configIdsUsed]
+    .map((cid) => {
+      const node = nodes.find((n) => n.id === cid)
+      return getConfigContent((node?.data ?? undefined) as Record<string, unknown> | undefined)
+    })
+    .join('\x00')
+  const allFunctionBodies = [...functionIdsToRegister]
+    .map((fid) => {
+      const node = nodes.find((n) => n.id === fid)
+      return ((node?.data as Record<string, unknown>)?.body as string) ?? ''
+    })
+    .join('\x00')
+  const cacheKey = `${srcId}\x01${JSON.stringify(nunjucksContext)}\x01${allTemplateContents}\x01${allFunctionBodies}`
+
+  const cached = resolveCache.get(cacheKey)
+  if (cached) return cached
+
+  const env = new nunjucks.Environment([configLoader], { autoescape: false })
+
+  const formatFilterResult = (r: unknown): string => {
+    if (r === undefined || r === null) return ''
+    if (typeof r === 'string' || typeof r === 'number' || typeof r === 'boolean') return String(r)
+    return String(r)
+  }
+  const parseFunctionSignature = (body: string): { paramNames: string[]; innerBody: string } | null => {
+    const withCommentsStripped = body.replace(/^\s*\/\/[^\n]*\n?/gm, '').trim()
+    const trimmed = withCommentsStripped.trim()
+    const fnMatch = trimmed.match(/^function\s*\(([^)]*)\)\s*\{([\s\S]*)\}\s*$/)
+    if (fnMatch) {
+      const paramNames = fnMatch[1].split(',').map((p) => p.trim()).filter(Boolean)
+      return { paramNames, innerBody: fnMatch[2].trim() }
+    }
+    const arrowBlockMatch = trimmed.match(/^\(([^)]*)\)\s*=>\s*\{([\s\S]*)\}\s*$/)
+    if (arrowBlockMatch) {
+      const paramNames = arrowBlockMatch[1].split(',').map((p) => p.trim()).filter(Boolean)
+      return { paramNames, innerBody: arrowBlockMatch[2].trim() }
+    }
+    const arrowExprMatch = trimmed.match(/^\(([^)]*)\)\s*=>\s*(.+)\s*$/s)
+    if (arrowExprMatch) {
+      const paramNames = arrowExprMatch[1].split(',').map((p) => p.trim()).filter(Boolean)
+      return { paramNames, innerBody: 'return ' + arrowExprMatch[2].trim() }
+    }
+    return null
+  }
+  const isPlainObject = (v: unknown): v is Record<string, unknown> =>
+    typeof v === 'object' && v !== null && !Array.isArray(v)
+
+  const functionConnectedVariableIds = Object.create(null) as Record<string, string[]>
+  const functionConnectedFunctionIds = Object.create(null) as Record<string, string[]>
+  for (const fid of functionIdsToRegister) {
+    for (const e of edges) {
+      if (e.target !== fid) continue
+      const src = nodes.find((n) => n.id === e.source)
+      if (src?.type === 'variable') {
+        if (!functionConnectedVariableIds[fid]) functionConnectedVariableIds[fid] = []
+        functionConnectedVariableIds[fid].push(src.id)
+      } else if (src?.type === 'function') {
+        if (!functionConnectedFunctionIds[fid]) functionConnectedFunctionIds[fid] = []
+        functionConnectedFunctionIds[fid].push(src.id)
+      }
+    }
+  }
+
+  for (const fid of functionIdsToRegister) {
+    const src = nodes.find((n) => n.id === fid)
+    if (!src || src.type !== 'function') continue
+    const body = ((src.data as Record<string, unknown>)?.body as string) ?? 'return args[0];'
+    const parsed = parseFunctionSignature(body)
+    const connectedVarIds = new Set<string>(functionConnectedVariableIds[fid] ?? [])
+    const connectedFuncIds = functionConnectedFunctionIds[fid] ?? []
+    env.addFilter(
+      src.id,
+      (value: unknown, ...args: unknown[]) => {
+        const callback = args[args.length - 1] as (err: Error | null, res: string) => void
+        const raw = [value, ...args.slice(0, -1)]
+        const hasKwargs = raw.length > 0 && isPlainObject(raw[raw.length - 1])
+        const positionals = hasKwargs ? raw.slice(0, -1) : raw
+        const kwargs = hasKwargs ? (raw[raw.length - 1] as Record<string, unknown>) : Object.create(null)
+
+        const nestedCache = new Map<string, string>()
+        const coerceCached = (s: string): string | number => {
+          const n = Number(s)
+          return s.trim() !== '' && !Number.isNaN(n) ? n : s
+        }
+        const makeCallable = (filterId: string) => (input: unknown) => {
+          const key = `${filterId}::${JSON.stringify(input)}`
+          if (nestedCache.has(key)) return coerceCached(nestedCache.get(key)!)
+          const p = new Promise<string>((resolve, reject) => {
+            env.getFilter(filterId)(input, (err: Error | null, res: string) =>
+              err ? reject(err) : resolve(res)
+            )
+          })
+          p.then((res) => nestedCache.set(key, res))
+          const suspend = { __suspend: true as const, promise: p, key }
+          throw suspend
+        }
+
+        let invoke: () => unknown
+        if (parsed) {
+          const { paramNames, innerBody } = parsed
+          const lastParam = paramNames[paramNames.length - 1]
+          const invocationArgs = paramNames.map((name, i) => {
+            if (name === lastParam && lastParam === 'kwargs') return kwargs
+            if (connectedVarIds.has(name) && name in nunjucksContext) return nunjucksContext[name]
+            if (connectedFuncIds.includes(name)) return makeCallable(name)
+            return positionals[i]
+          })
+          const extraVarIds = [...connectedVarIds].filter((vid) => !paramNames.includes(vid))
+          const extraFuncIds = connectedFuncIds.filter((fid2) => !paramNames.includes(fid2))
+          const allParamNames = [...paramNames, ...extraVarIds, ...extraFuncIds]
+          const allArgs = [
+            ...invocationArgs,
+            ...extraVarIds.map((vid) => nunjucksContext[vid]),
+            ...extraFuncIds.map((fid2) => makeCallable(fid2)),
+          ]
+          const fn = new Function(...allParamNames, innerBody)
+          invoke = () => fn(...allArgs)
+        } else {
+          const fn = new Function('args', body)
+          invoke = () => fn(positionals)
+        }
+
+        const done = (err: Error | null, res: string) => callback(err, res)
+        const runInvoke = () => {
+          try {
+            const result = invoke()
+            if (result != null && typeof (result as Promise<unknown>).then === 'function') {
+              (result as Promise<unknown>).then(
+                (r) => done(null, formatFilterResult(r)),
+                (err) => done(err instanceof Error ? err : new Error(String(err)), '')
+              )
+            } else {
+              done(null, formatFilterResult(result))
+            }
+          } catch (e: unknown) {
+            const s = e as { __suspend?: boolean; promise?: Promise<string>; key?: string }
+            if (s?.__suspend && s.promise) {
+              s.promise.then(() => runInvoke(), (err) =>
+                done(err instanceof Error ? err : new Error(String(err)), '')
+              )
+            } else {
+              done(e instanceof Error ? e : new Error(String(e)), '')
+            }
+          }
+        }
+        runInvoke()
+      },
+      true
+    )
+  }
+
+  return new Promise((resolve, reject) => {
+    env.render(srcId, nunjucksContext, (nunjucksErr: Error | null, afterNunjucks: string) => {
+      if (nunjucksErr) {
+        reject(new Error(`Nunjucks: ${nunjucksErr.message}`))
+        return
+      }
+      const resolved = afterNunjucks.replace(/(\r?\n)(\s*\r?\n)+/g, '$1').trim()
+      const result: ResolvedContentResult = { resolved, outputTypeId }
+      // FIFO eviction when cache is full
+      if (resolveCache.size >= MAX_RESOLVE_CACHE) {
+        resolveCache.delete(resolveCache.keys().next().value as string)
+      }
+      resolveCache.set(cacheKey, result)
+      resolve(result)
+    })
+  })
+}

frontend/src/components/nodes/data/DataNode.tsx

@@ -0,0 +1,363 @@
+import React, { useCallback, useContext, useMemo, useRef, useState } from 'react'
+import {
+    AbstractNodeProps,
+    createAbstractNodeComponent,
+    useAbstractNode,
+} from '@/lib/graph/abstractNode'
+import {
+    BaseNode,
+    BaseNodeContent,
+    BaseNodeFooter,
+    BaseNodeHeaderRow,
+} from '@/components/graph/BaseNode'
+import { NodeFooterEdgeIndicators } from '@/components/graph/NodeFooterEdgeIndicators'
+import { NodeHeaderTitle } from '@/components/graph/NodeHeaderTitle'
+import { NodeMenubar } from '@/components/graph/NodeMenubar'
+import { FlowUIContext } from '@/lib/graph/flowContext'
+import { getNodeType } from '@/lib/graph/nodeRegistry'
+import { OutputHandle } from '@/components/graph/NodeHandles'
+import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from '@/components/ui/table'
+import { parseCsvToRows } from '@/lib/csvParse'
+import { ArrowDown, ArrowUp, ArrowUpDown, Database, FileUp } from 'lucide-react'
+import {
+    flexRender,
+    getCoreRowModel,
+    getFilteredRowModel,
+    getPaginationRowModel,
+    getSortedRowModel,
+    useReactTable,
+    type ColumnDef,
+    type SortingState,
+} from '@tanstack/react-table'
+import { Button } from '@/components/ui/button'
+import { Input } from '@/components/ui/input'
+import { ContextMenuCheckboxItem } from '@/components/ui/context-menu'
+import {
+    MenubarCheckboxItem,
+    MenubarItem,
+    MenubarSeparator,
+    MenubarSub,
+    MenubarSubContent,
+    MenubarSubTrigger,
+} from '@/components/ui/menubar'
+
+export type DataNodeData = {
+    rows?: Record<string, string>[]
+    columns?: string[]
+    fileName?: string
+    /** Column ids (header names) that are hidden; hidden columns are excluded from template output */
+    hiddenColumns?: string[]
+}
+
+type Props = AbstractNodeProps<DataNodeData>
+
+function DataNodeComponent({ id, data, width, height, selected }: Props) {
+    const flowUIContext = useContext(FlowUIContext)
+    const setFullscreenNodeId = flowUIContext?.setFullscreenNodeId
+    const supportsFullscreen = getNodeType('data')?.supportsFullscreen
+    const { updateData } = useAbstractNode<DataNodeData>(id, data ?? {})
+    const rows = data?.rows ?? []
+    const columns = data?.columns ?? []
+    const hiddenColumns = data?.hiddenColumns ?? []
+    const [isDragging, setIsDragging] = useState(false)
+    const [globalFilter, setGlobalFilter] = useState('')
+    const [sorting, setSorting] = useState<SortingState>([])
+    const fileInputRef = useRef<HTMLInputElement>(null)
+    const hasData = rows.length > 0 && columns.length > 0
+
+    const onFile = useCallback(
+        (file: File) => {
+            if (!file.name.toLowerCase().endsWith('.csv')) return
+            const reader = new FileReader()
+            reader.onload = () => {
+                try {
+                    const text = (reader.result as string) ?? ''
+                    const { columns: cols, rows: parsed } = parseCsvToRows(text)
+                    updateData({ rows: parsed, columns: cols, fileName: file.name, hiddenColumns: [] })
+                } catch {
+                    updateData({ rows: [], columns: [], fileName: '', hiddenColumns: [] })
+                }
+            }
+            reader.readAsText(file)
+        },
+        [updateData]
+    )
+
+    const onDrop = useCallback(
+        (e: React.DragEvent) => {
+            e.preventDefault()
+            setIsDragging(false)
+            const file = e.dataTransfer?.files?.[0]
+            if (file) onFile(file)
+        },
+        [onFile]
+    )
+
+    const onDragOver = useCallback((e: React.DragEvent) => {
+        e.preventDefault()
+        e.dataTransfer.dropEffect = 'copy'
+        setIsDragging(true)
+    }, [])
+
+    const onDragLeave = useCallback(() => setIsDragging(false), [])
+
+    const onInputChange = useCallback(
+        (e: React.ChangeEvent<HTMLInputElement>) => {
+            const file = e.target.files?.[0]
+            if (file) onFile(file)
+            e.target.value = ''
+        },
+        [onFile]
+    )
+
+    const openFileDialog = useCallback(() => {
+        fileInputRef.current?.click()
+    }, [])
+
+    const clearData = useCallback(() => {
+        updateData({ rows: [], columns: [], fileName: '', hiddenColumns: [] })
+    }, [updateData])
+
+    const columnVisibility = useMemo(
+        () => Object.fromEntries(columns.map((col) => [col, !hiddenColumns.includes(col)])),
+        [columns, hiddenColumns]
+    )
+
+    const onColumnVisibilityChange = useCallback(
+        (updater: (prev: Record<string, boolean>) => Record<string, boolean>) => {
+            const next = updater(columnVisibility)
+            const newHidden = columns.filter((col) => !next[col])
+            updateData({ hiddenColumns: newHidden })
+        },
+        [columnVisibility, columns, updateData]
+    )
+
+    const tableColumns = useMemo<ColumnDef<Record<string, string>>[]>(() => {
+        return columns.map((key) => ({
+            accessorKey: key,
+            header: ({ column }: { column: { getIsSorted: () => false | 'asc' | 'desc'; toggleSorting: (desc: boolean) => void } }) => (
+                <Button
+                    variant="ghost"
+                    size="sm"
+                    className="-ml-2 h-8 data-[state=open]:bg-accent"
+                    onClick={() => column.toggleSorting(column.getIsSorted() === 'asc')}
+                >
+                    {key}
+                    {column.getIsSorted() === 'desc' ? (
+                        <ArrowDown className="ml-1.5 size-3.5" />
+                    ) : column.getIsSorted() === 'asc' ? (
+                        <ArrowUp className="ml-1.5 size-3.5" />
+                    ) : (
+                        <ArrowUpDown className="ml-1.5 size-3.5" />
+                    )}
+                </Button>
+            ),
+            cell: ({ row }: { row: { getValue: (key: string) => unknown } }) => (
+                <span className="truncate max-w-[200px] block" title={String(row.getValue(key) ?? '')}>
+                    {String(row.getValue(key) ?? '')}
+                </span>
+            ),
+        }))
+    }, [columns])
+
+    const table = useReactTable({
+        data: rows,
+        columns: tableColumns,
+        getCoreRowModel: getCoreRowModel(),
+        getPaginationRowModel: getPaginationRowModel(),
+        getSortedRowModel: getSortedRowModel(),
+        getFilteredRowModel: getFilteredRowModel(),
+        onSortingChange: setSorting,
+        onColumnVisibilityChange,
+        onGlobalFilterChange: setGlobalFilter,
+        state: {
+            sorting,
+            columnVisibility,
+            globalFilter,
+        },
+        globalFilterFn: (row, _columnIds, filterValue) => {
+            const str = String(filterValue ?? '').toLowerCase()
+            if (!str) return true
+            const obj = row.original as Record<string, unknown>
+            for (const v of Object.values(obj)) {
+                if (String(v ?? '').toLowerCase().includes(str)) return true
+            }
+            return false
+        },
+    })
+
+    const fileInputId = `data-node-file-${id}`
+
+    const dataMenuContent = (
+        <>
+            <MenubarItem className="text-xs" onClick={openFileDialog}>
+                Upload new dataset
+            </MenubarItem>
+            <MenubarItem className="text-xs" onClick={clearData}>
+                Clear dataset
+            </MenubarItem>
+            {hasData && (
+                <>
+                    <MenubarSeparator />
+                    <MenubarSub>
+                        <MenubarSubTrigger className="text-xs">Columns</MenubarSubTrigger>
+                        <MenubarSubContent className="min-w-[10rem]">
+                            {table
+                                .getAllColumns()
+                                .filter((col) => typeof col.accessorFn !== 'undefined' && col.getCanHide())
+                                .map((col) => (
+                                    <MenubarCheckboxItem
+                                        key={col.id}
+                                        className="text-xs capitalize"
+                                        checked={col.getIsVisible()}
+                                        onCheckedChange={(value) => col.toggleVisibility(!!value)}
+                                    >
+                                        {col.id}
+                                    </MenubarCheckboxItem>
+                                ))}
+                        </MenubarSubContent>
+                    </MenubarSub>
+                    <MenubarSub>
+                        <MenubarSubTrigger className="text-xs">Rows per page</MenubarSubTrigger>
+                        <MenubarSubContent className="min-w-[8rem]">
+                            {[10, 20, 30, 50].map((size) => (
+                                <ContextMenuCheckboxItem
+                                    key={size}
+                                    className="text-xs"
+                                    checked={table.getState().pagination.pageSize === size}
+                                    onCheckedChange={() => table.setPageSize(size)}
+                                >
+                                    {size}
+                                </ContextMenuCheckboxItem>
+                            ))}
+                        </MenubarSubContent>
+                    </MenubarSub>
+                </>
+            )}
+        </>
+    )
+
+    const dimensions =
+        width != null && height != null && width > 0 && height > 0
+            ? { width, height }
+            : undefined
+
+    return (
+        <BaseNode className="min-w-[320px] min-h-[200px]" dimensions={dimensions} resizable nodeId={id} selected={selected} handles={<OutputHandle id="out" />}>
+            <input
+                id={fileInputId}
+                ref={fileInputRef}
+                type="file"
+                accept=".csv"
+                onChange={onInputChange}
+                className="sr-only"
+                aria-label="Upload CSV file"
+            />
+            <BaseNodeHeaderRow
+                icon={<Database className="size-4" />}
+                title={<NodeHeaderTitle nodeId={id} displayTitle={id} />}
+                onHeaderDoubleClick={supportsFullscreen && setFullscreenNodeId ? () => setFullscreenNodeId(id) : undefined}
+            />
+
+            <BaseNodeContent>
+                <div className="shrink-0 w-full">
+                    <NodeMenubar nodeId={id} nodeType="data" dataMenuContent={dataMenuContent} />
+                </div>
+                {!hasData ? (
+                    <label
+                        htmlFor={fileInputId}
+                        className={`flex-1 min-h-[140px] flex flex-col items-center justify-center gap-2 rounded-md border-2 border-dashed p-4 m-2 transition-colors nodrag nopan cursor-pointer ${isDragging ? 'border-primary bg-primary/5' : 'border-muted-foreground/25'
+                            }`}
+                        onDrop={onDrop}
+                        onDragOver={onDragOver}
+                        onDragLeave={onDragLeave}
+                    >
+                        <FileUp className="size-8 text-muted-foreground" />
+                        <p className="text-xs text-muted-foreground text-center">
+                            Drop a .csv file here or click to browse
+                        </p>
+                    </label>
+                ) : (
+                    <div className="flex min-h-0 flex-1 flex-col gap-2 pt-2 nodrag nopan">
+                        <div className="flex shrink-0 flex-wrap items-center gap-2 px-2">
+                            <Input
+                                placeholder="Search..."
+                                value={globalFilter}
+                                onChange={(e) => setGlobalFilter(e.target.value)}
+                                className="h-8 max-w-[180px] text-xs"
+                            />
+                            <div className="ml-auto flex items-center gap-2">
+                                <span className="text-xs text-muted-foreground">
+                                    {table.getState().pagination.pageIndex + 1} of {table.getPageCount()}
+                                </span>
+                                <Button
+                                    variant="outline"
+                                    size="sm"
+                                    className="h-8 w-8 p-0"
+                                    onClick={() => table.previousPage()}
+                                    disabled={!table.getCanPreviousPage()}
+                                >
+                                    ←
+                                </Button>
+                                <Button
+                                    variant="outline"
+                                    size="sm"
+                                    className="h-8 w-8 p-0"
+                                    onClick={() => table.nextPage()}
+                                    disabled={!table.getCanNextPage()}
+                                >
+                                    →
+                                </Button>
+                            </div>
+                        </div>
+                        <div className="min-h-0 flex-1 overflow-auto">
+                            <Table>
+                                <TableHeader>
+                                    {table.getHeaderGroups().map((headerGroup) => (
+                                        <TableRow key={headerGroup.id}>
+                                            {headerGroup.headers.map((header) => (
+                                                <TableHead key={header.id} className="whitespace-nowrap">
+                                                    {flexRender(header.column.columnDef.header, header.getContext())}
+                                                </TableHead>
+                                            ))}
+                                        </TableRow>
+                                    ))}
+                                </TableHeader>
+                                <TableBody>
+                                    {table.getRowModel().rows?.length ? (
+                                        table.getRowModel().rows.map((row) => (
+                                            <TableRow key={row.id}>
+                                                {row.getVisibleCells().map((cell) => (
+                                                    <TableCell key={cell.id} className="whitespace-nowrap">
+                                                        {flexRender(cell.column.columnDef.cell, cell.getContext())}
+                                                    </TableCell>
+                                                ))}
+                                            </TableRow>
+                                        ))
+                                    ) : (
+                                        <TableRow>
+                                            <TableCell colSpan={columns.length} className="h-16 text-center text-muted-foreground text-xs">
+                                                No results.
+                                            </TableCell>
+                                        </TableRow>
+                                    )}
+                                </TableBody>
+                            </Table>
+                        </div>
+                    </div>
+                )}
+            </BaseNodeContent>
+
+            <BaseNodeFooter>
+                <NodeFooterEdgeIndicators nodeId={id} nodeType="data">
+                    {hasData
+                        ? `${table.getFilteredRowModel().rows.length} of ${rows.length} rows · ${table.getVisibleLeafColumns().length} cols`
+                        : 'Drop CSV'}
+                </NodeFooterEdgeIndicators>
+            </BaseNodeFooter>
+        </BaseNode>
+    )
+}
+
+export const DataNode = createAbstractNodeComponent<DataNodeData>('DataNode', DataNodeComponent)
+export default DataNode

frontend/src/components/nodes/data/descriptor.tsx

@@ -0,0 +1,26 @@
+import React from 'react'
+import { Database } from 'lucide-react'
+import { createNodeTypeBuilder } from '@/lib/graph/nodeTypeBuilder'
+import { NODE_HELP } from '@/lib/graph/nodeHelp'
+import type { NodeTypeDescriptor } from '@/lib/graph/nodeRegistry'
+import DataNode from './DataNode'
+
+const ICON_CLASS = 'mr-2 h-4 w-4'
+
+export function getDataNodeDescriptor(): NodeTypeDescriptor {
+  return createNodeTypeBuilder(
+    'data',
+    DataNode,
+    { width: 360, height: 280 },
+    { rows: [], columns: [], fileName: '' }
+  )
+    .idPrefix('data_')
+    .withInputOutput(false, true)
+    .classification('physis')
+    .allowedTargetTypes(['config', 'agent'])
+    .help(NODE_HELP.data)
+    .menu('Data', <Database className={ICON_CLASS} />)
+    .connectionLabelByStatus({ default: 'data source' })
+    .withFullscreen()
+    .build()
+}

frontend/src/components/nodes/data/index.ts

@@ -0,0 +1,2 @@
+export { default as DataNode, type DataNodeData } from './DataNode'
+export { getDataNodeDescriptor } from './descriptor'