ADR 0001: TeeTime adopted (NestJS modular architecture)

• Status: accepted
• Date: 2025-10-03

Context

TeeTime spans multiple apps (backend APIs, admin portal, public UI, workers) and needs a consistent way to:

• enforce auth and access control,
• share domain services (tee-sheet, booking, weather, messaging),
• emit real-time events (WebSocket/SSE) and durable events (outbox),
• keep “core” logic reusable across apps without duplicating controllers/services.

Decision

Adopt a modular NestJS architecture where:

• cross-cutting auth/guards live in libs/auth,
• shared tee-time domain services + façade controllers live in libs/tee-time-services,
• the backend app (apps/teetime/teetime-backend) composes those libs and owns:
  • app bootstrap and global middleware,
  • admin-only controllers that are tightly coupled to the deployed backend,
  • Swagger configuration and operational endpoints.

This docs site (apps/teetime/docs) is the canonical reference for implementers and operators.

Consequences

Positive:

• Shared logic is implemented once and reused across apps.
• Controllers stay thin and delegate to services with explicit contracts.
• Real-time and messaging integrations can be feature-flagged and no-op safely when optional dependencies are absent.

Trade-offs:

• Requires discipline around module boundaries and dependency wiring.
• Some endpoints are defined in libraries but are only “real” when the backend app includes the relevant module/providers.

References

• libs/auth
• libs/tee-time-services
• apps/teetime/teetime-backend/src/main.ts
• apps/teetime/docs