Scaffold Backend

Scaffold Backend

Generate a minimal, working backend from the confirmed PRD. The backend should be callable immediately by the frontend, even if persistence is temporary.

Preflight

Check from the repo root:

test -f AGENTS.md && test -f PRD.md || { echo MISSING_DOCS; exit 1; }
test -d server && echo SERVER_EXISTS || true

Read PRD.md > Backend Needed?.

Stop without creating files if:

• AGENTS.md or PRD.md is missing
• Backend Needed? is missing, empty, or starts with No
• server/ already exists and is non-empty
• Backend Routes is empty even though backend is needed

In each stop case, explain the specific missing prerequisite and the safest next step.

Read The Specs

Extract:

• Backend routes, each as method, path, and purpose
• Data model entities and fields
• Auth, storage, file processing, email, and paid API requirements
• Domain constraints that affect validation
• Python version and backend conventions from AGENTS.md

If the PRD implies a database, ask whether to wire Supabase now, defer it, or use an in-memory placeholder. Do not silently choose paid or external services.

Before generating files, make a route inventory table with Method, Path, Purpose, Route Module, and Handler. This table is the contract for the scaffold. If two PRD bullets map to the same handler or an entity has no route module, resolve that before writing files.

Create server/

Generate:

server/
  app/
    __init__.py
    main.py
    config.py
    db.py
    models.py
    routes/
      __init__.py
      health.py
      <entity>.py
  tests/
    __init__.py
    test_health.py
  .env.example
  .gitignore
  requirements.txt
  README.md

Include:

• FastAPI app with CORS for http://localhost:3000
• GET /health
• One route module per entity or route group in Backend Routes
• Pydantic Base, Create, and response models for each entity
• Type-safe placeholder data with UUIDs
• Supabase client only if the user chose it

Avoid NotImplementedError stubs. The frontend should be able to call routes and receive realistic dummy responses.

Dependencies

Include:

fastapi>=0.115
uvicorn[standard]>=0.32
pydantic>=2.9
pydantic-settings>=2.6
python-dotenv>=1.0
pytest>=8.3
httpx>=0.27

Add supabase>=2.9 only if Supabase is selected.

Route Generation Rules

For each PRD route:

• Match the HTTP method and path exactly.
• Use descriptive function names.
• Return typed models or lists of typed models.
• Raise HTTPException(status_code=404) for missing IDs.
• Keep route behavior simple and predictable.
• Add comments only where the placeholder store needs future replacement.

GET /health is allowed as a scaffold health check, but it does not count as satisfying a PRD route. In the final response, separate health routes from product routes so the user can see exactly what came from the PRD.

Verify

From server/:

python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
pytest
uvicorn app.main:app --reload

Confirm:

• Tests pass
• GET /health returns {"status": "ok"}
• Generated routes appear in /docs
• No secrets are hardcoded

If verification fails, switch to the bugfix workflow and fix the generated scaffold before reporting success.

Final Response

Return:

1. Files Created: every file under server/
2. Routes Generated: each PRD route and generated handler
3. Health Check: GET /health status, listed separately from PRD product routes
4. Persistence: Supabase or in-memory placeholder, with reason
5. Verification: commands and outcomes
6. Next Steps: update frontend API URL and connect the first feature

Boundaries

• Do not run without the required docs.
• Do not create a backend when the PRD says no backend.
• Do not overwrite existing backend files without approval.
• Do not invent routes outside the PRD.
• Do not hardcode secrets.