nestjs-expert

Prevent circular dependencies in Nest.js by establishing clear module boundaries and using forward references with proper provider scopes. This approach maintains a modular structure and resolves injection loops.

In Nest.js, the execution order is middleware, guards, interceptors, and pipes. Guards handle authorization, interceptors manage logging and transformation, and pipes process data validation before the route handler executes.

Set up JWT authentication in Nest.js by integrating Passport.js strategies. Configure the auth module with secure token generation and validation guards to protect endpoints and verify user identity across requests.

Write e2e tests for Nest.js using @nestjs/testing alongside Jest and Supertest. Compile the testing module to simulate HTTP requests, verifying integration across modules, database connections, and authentication flows.

Yes, Nest.js supports integrating both TypeORM and Mongoose in the same project. You can configure distinct database modules to handle relational and non-relational data stores simultaneously within your architecture.

The best way to structure a scalable enterprise Nest.js app is through modular architecture. Define distinct feature modules, manage dependency injection scopes, and separate business logic into providers to ensure maintainability.