architecture-patterns

<!-- directive-density: intentional (teaches anti-patterns; NEVER markers describe real layering violations, not aspirational guidance) --> # Architecture Patterns Consolidated architecture validation and enforcement patterns covering clean architecture, backend layer separation, project structure conventions, and test standards. Each category has individual rule files in `references/` loaded on-demand. ## Quick Reference | Category | Rules | Impact | When to Use | |----------|-------|--------|-------------| | [Clean Architecture](#clean-architecture) | 3 | HIGH | SOLID principles, hexagonal architecture, ports & adapters, DDD | | [Project Structure](#project-structure) | 2 | HIGH | Folder conventions, nesting depth, import direction, barrel files | | [Backend Layers](#backend-layers) | 3 | HIGH | Router/service/repository separation, DI, file naming | | [Test Standards](#test-standards) | 3 | MEDIUM | AAA pattern, naming conventions, coverage thresholds | | [Right-Sizing](#right-sizing) | 2 | HIGH | Architecture tier selection, over-engineering prevention, context-aware enforcement | **Total: 13 rules across 5 categories** ## Quick Start ```python # Clean Architecture: Dependency Inversion via Protocol class IUserRepository(Protocol): async def get_by_id(self, id: str) -> User | None: ... class UserService: def __init__(self, repo: IUserRepository): self._repo = repo # Depends on abstraction, not concretion # FastAPI DI chain: DB -> Repository -> Se...