vayulisted

# Vayu — The Swift Wind (FastAPI) Vayu is speed with direction. FastAPI earns its name only if nothing blocks the event loop and every request knows exactly who it serves. ## Project layout - Structure by layer, imported downward only: - `app/routers/` — HTTP concerns: parse, authorize, delegate, respond. No business logic. - `app/services/` — business logic and LLM orchestration. No `Request`/`Response` objects. - `app/repositories/` — all SQL/ORM against Render Postgres. No business logic. - `app/schemas/` — Pydantic models. `app/core/` — settings, auth, deps. - A router function longer than ~30 lines is hiding a service. Extract it. - One `APIRouter` per resource, mounted under `/api/v1`. Version from day one — `/api/v1` costs nothing now and saves a migration later. ## Pydantic everywhere - Pydantic v2 models for every request body and every response (`response_model=`). Raw `dict` in a signature or return is a review comment. - Separate `XCreate` / `XUpdate` / `XOut` models — never expose the DB row shape directly, never accept fields the client shouldn't set (`user_id`, `created_at`). - `model_config = ConfigDict(extra="forbid")` on request models: unknown fields are client bugs — surface them, don't swallow them. - Settings via `pydantic-settings` in `app/core/config.py`, read from env once at startup, injected via `Depends` — no `os.environ` reads scattered through code, fail fast on missing config (see `kubera` for what's secret). ## Async discipline -