nestjs-conventions

NestJS backend conventions standardize feature-based modules with separate module.ts, controller.ts, service.ts, entities, and dto/ folders. This modular structure isolates domain logic, ensuring consistent code quality and separation of concerns across your project.

To validate DTOs in NestJS, always define them with class-validator and separate create, update, and response variations. This approach ensures incoming data matches expected schemas while providing English validation messages to standardize error handling across endpoints.

Yes, these NestJS backend conventions apply to both new and existing projects during implementation and code review. You can incrementally refactor legacy code to satisfy requirements for modular structure, typed config usage, and standardized error handling.

Manage NestJS database migrations using TypeORM CLI and load typed configurations via @nestjs/config to avoid hardcoded secrets. This discipline ensures environment-specific settings are safely injected through dependency injection rather than scattered inline.

Use shared guards and interceptors in NestJS when you need to standardize authentication, authorization, or response transformation across modules. Applying these via dependency injection ensures separation of concerns and prevents duplicated logic across controllers.