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+# PM — Project Management MVP
+
+A Kanban board with an AI chat sidebar. A Next.js frontend (built as a static export) is served by a FastAPI backend from a single process on a single port.
+
+## Architecture
+
+- **Monorepo**: `frontend/` (Next.js), `backend/` (FastAPI), `scripts/` (start/stop/build), `docs/`.
+- **Single container, single port (8000)**: FastAPI serves both the API (`/api/*`) and the built frontend at `/` — there is no reverse proxy and no separate frontend server in production.
+- **Frontend**: a single-page app (Kanban board) with an `AuthGate` that switches between a login form and the board based on session state.
+- **Auth**: cookie-based sessions, one hardcoded demo user (`user` / `password`) — documented MVP limitation, not a bug.
+- **Data**: SQLite (`backend/data/app.db`), one JSON blob per user holding the whole board (columns + cards). Schema details in [`docs/DATABASE.md`](docs/DATABASE.md).
+- **AI chat**: calls OpenRouter (`openai/gpt-oss-120b`) to create/update/move/delete cards via structured output; it can never add, rename, or delete columns.
+
+## Quick start (Docker)
+
+Builds the image from the root `Dockerfile` and runs it as container `pm-app` on `http://localhost:8000`. Requires a project-root `.env` with `OPENROUTER_API_KEY`.
+
+| Platform | Start | Stop |
+|----------|-------|------|
+| Windows | `.\scripts\start-windows.ps1` | `.\scripts\stop-windows.ps1` |
+| macOS | `./scripts/start-mac.sh` | `./scripts/stop-mac.sh` |
+| Linux | `./scripts/start-linux.sh` | `./scripts/stop-linux.sh` |
+
+Or equivalently: `docker-compose up`.
+
+## Local development
+
+### Frontend (`frontend/`)
+
+```bash
+npm install
+npm run dev          # dev server at http://localhost:3000
+npm run build         # static export to frontend/out/
+npm run lint
+```
+
+### Backend (`backend/`)
+
+```bash
+uv sync --extra dev
+uv run uvicorn app.main:app --reload --port 8000   # requires OPENROUTER_API_KEY in project-root .env
+```
+
+Before running the backend directly (or any test that serves built HTML), build the frontend into `backend/static/`:
+
+```bash
+./scripts/build-frontend.ps1   # Windows
+./scripts/build-frontend.sh    # macOS/Linux
+```
+
+## Testing
+
+```bash
+# Frontend, from frontend/
+npm run test          # Vitest unit/component tests
+npm run test:e2e       # Playwright e2e (launches the FastAPI backend itself; requires uv)
+npm run test:all       # both
+
+# Backend, from backend/
+uv run pytest
+```
+
+## Tech stack
+
+| Layer | Tools |
+|-------|-------|
+| Frontend | Next.js, React, Tailwind CSS, @dnd-kit, Vitest, Playwright |
+| Backend | FastAPI, uvicorn, SQLAlchemy, SQLite, httpx, uv, pytest |
+| AI | OpenRouter (`openai/gpt-oss-120b`) |
+| Packaging | Docker (single image, single port) |
+
+## More detail
+
+- [`frontend/AGENTS.md`](frontend/AGENTS.md) — frontend structure, components, data model
+- [`backend/AGENTS.md`](backend/AGENTS.md) — API routes, auth, AI integration
+- [`scripts/AGENTS.md`](scripts/AGENTS.md) — start/stop/build scripts
+- [`docs/DATABASE.md`](docs/DATABASE.md) — schema and seed data
+- [`docs/PLAN.md`](docs/PLAN.md) — phased implementation history/roadmap
+- [`CLAUDE.md`](CLAUDE.md) — full project guide (architecture, commands, coding standards)