platform-buildlisted

# Platform Build Task (Stage 4) Use this skill when you are the Platform Developer executing the Stage 4 build stage — setting up infra, CI, and the deploy rails for a new feature. ## Procedure 1. Read `pipeline/design-spec.md` — set up infra, CI, and root toolchain config to support what's being built. 2. Append an `## Assumptions` block to `pipeline/context.md` for non-obvious infra choices (ports, volumes, healthcheck targets) per coding-principles §1. Write the **Plan** preamble at the top of `pipeline/pr-platform.md` per §4. 3. Write or update `docker-compose.yml` in the project root: - Define a service for each component in the design spec - Add a `healthcheck:` to every HTTP service so `docker compose up --wait` works - Use `.env` for all secrets and environment-specific values — never hardcode - Mount source directories as volumes for local dev hot-reload where appropriate 4. Write or update any supporting infra/toolchain config (`.env.example`, nginx config, `package.json` scripts, lockfiles, ESLint/TypeScript config, Docker/compose files, etc.). Root package-manager scripts and shared toolchain config are platform-owned unless the design spec or a Principal ruling assigns them elsewhere. If `npm run lint` is missing, add the script and any minimal config needed for Stage 4a to run it mechanically. Keep source-code changes inside `src/infra/`; cross-boundary edits need a `CONCERN:` line first (coding-principles §3). 5. Fin