# 03 — Drizzle + Postgres setup

## Goal

Wire Drizzle ORM to a Postgres 16 instance, with migrations and a working `db` client.

## Depends on

- 02 (Next.js skeleton)

## Scope

- Install `drizzle-orm`, `drizzle-kit`, `postgres` (the `postgres` driver, not `pg`).
- `drizzle.config.ts` pointing at `src/modules/**/schema.ts` and writing to `./drizzle/`.
- `src/lib/db.ts` exporting a singleton `db` client built from `DATABASE_URL`.
- Initial schema in `src/modules/_core/schema.ts`:
  - `users` (id uuid pk, email unique, display_name, created_at)
  - `households` (id uuid pk, name, created_at)
  - `household_members` (household_id, user_id, role enum: `owner` | `member`, pk on both)
- pnpm scripts: `db:generate`, `db:migrate`, `db:studio`.
- `docker-compose.dev.yaml` at repo root with a `famapp-db` service for local dev (Postgres 16, exposed on 5432, named volume).

## Out of scope

- Module-specific tables (calendar/lists/notes ship in their own tasks).
- Seed data (in task 07).

## Acceptance criteria

- [ ] `docker compose -f docker-compose.dev.yaml up -d` starts Postgres locally.
- [ ] `pnpm db:generate && pnpm db:migrate` produces `drizzle/0000_*.sql` and applies it.
- [ ] A throwaway script can `import { db } from "@/lib/db"` and `select` from `users` (returning empty).
- [ ] `tsc --noEmit` passes.

## Notes

- Use the `postgres` driver — works in both Node and edge-light contexts and is what Drizzle docs prefer for serverless-shaped apps.
- Keep the dev compose file separate from the production `deploy/compose.yaml` (task 05).