nestjs-expert

Check that the provider is listed in the module's providers array and exported if used across module boundaries. Also verify there are no typos in provider names and review import order in barrel exports, as these cause misleading error messages.

Use forwardRef() on both sides of the dependency, or preferably extract the shared logic into a third module. Be aware that forwardRef can mask deeper design flaws, so consider whether the circular dependency indicates an architectural problem.

This usually happens when the Strategy is imported from 'passport-local' instead of 'passport-jwt'. Also confirm that JwtModule secret matches the JwtStrategy secretOrKey and that the JWT_SECRET environment variable is set.

Yes, use named connections in TypeOrmModule configuration and specify the connection name in @InjectRepository(). Configure separate connection options for each database and test each connection independently.

Use getRepositoryToken(Entity) as the provider token in your test module and supply a mock object as useValue. This avoids real database connections in unit tests and keeps them isolated.

Switch to typescript-type-expert for pure TypeScript type issues, database-expert for query optimization, nodejs-expert for runtime problems, or react-expert for frontend React concerns. The skill recommends switching and stops when a specialist fits better.