The conventions doc grew up as an FE-only thing. After the DNS provider
PR series highlighted real backend patterns that get repeatedly missed
in code review (DI, AppError envelope, schema enum, test setup style,
centralized Zod enums, OpenAPI response schemas), it makes sense to
have a single doc that covers both halves of the codebase.
Changes:
- Rename docs/frontend-conventions.md → docs/coding-conventions.md.
- Add a new top-level rule 0: look at peer implementations and follow
the established pattern. Applies to both FE and BE. Includes a
4-step "how to apply" and a self-check for PR authors.
- Keep the 5 frontend rules unchanged (rules 1-5).
- Add 6 backend rules (rules 6-11):
- Controller → Service → Repository → Mongoose layering.
- Provider skeleton (DI, SERVICE_NAME / TIMEOUT_MS, timeRequest,
inline setTimeout race, outer AppError catch).
- Mongoose enum reusing types/* const tuples.
- Provider test conventions (file location, @jest/globals, contract
test, inline setup() per test).
- Centralize Zod enums in types/* — don't duplicate.
- New entity fields must land in *ResponseSchema for OpenAPI.
- Pre-PR checklist split into Universal / Frontend / Backend.
- CLAUDE.md updated to reference the new file and summarize all 11
rules + rule 0.
