NestJS Cheat Sheet 2026

The 30 highest-yield NestJS facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What are the capabilities of a module described as? → A collection of closely related capabilities
2. What is the importance of data security in NestJS digital applications? → Protecting sensitive information from unauthorized access, breaches, and loss is essential
3. How do you make a single route publicly accessible when JWT auth is applied globally in NestJS? → Use a custom @Public() decorator combined with a reflector check in the guard
4. What does NestJS support? → GraphQL and WebSockets
5. Which method must be called after `Test.createTestingModule()` to finalize the module for use in tests? → .compile()
6. What is the role of the `AppModule` in a NestJS application? → It serves as the root module that bootstraps the entire application
7. Which NestJS package provides JWT signing and verification utilities? → @nestjs/jwt
8. Which class do NestJS guards need to implement? → CanActivate
9. What does PWA stand for? → Progressive Web Application
10. How do you create a circular dependency between two NestJS providers without causing errors? → Use forwardRef() in both @Inject() decorators
11. What does Nest.JS provide for developers to get started? → Module, controller, service and a testing pile
12. Why is documentation important in NestJS risk management? → It creates an audit trail, supports decision-making, and demonstrates due diligence
13. What is the name of the built-in microservice abstraction? → NestJS
14. What is the benefit of standardized digital reporting in NestJS practice? → It ensures consistency, enables comparison, and facilitates regulatory compliance
15. When testing a NestJS service that uses a repository (TypeORM), what is the correct token to use with `getRepositoryToken(Entity)` in the test providers array? → The result of `getRepositoryToken(Entity)` from `@nestjs/typeorm`
16. Which package must be imported to use `Test.createTestingModule()` in a NestJS test file? → @nestjs/testing
17. Which NestJS built-in pipe should be used to prevent oversized request payloads? → The `rawBody` limit in NestFactory options
18. What is the benefit of interdisciplinary collaboration in NestJS practice? → It brings diverse expertise and perspectives that improve outcomes and innovation
19. What does a website's back end include? → Data
20. What is the primary purpose of `Test.createTestingModule()` in NestJS? → To create an isolated module context for testing
21. What does `TypeOrmModule.forFeature([Entity])` do in a feature module? → Registers the entity's repository so it can be injected in that module
22. What is the most effective communication approach for NestJS professionals? → Adapting communication style to the audience while maintaining accuracy and clarity
23. How do you override a provider in a NestJS `TestingModule` with a custom mock? → builder.overrideProvider(RealService).useValue(mockService)
24. What is an extension to the popular AngularJS framework? → NestJS cors
25. Which NestJS-compatible ORM uses a code-first approach with a schema builder instead of decorators? → Prisma
26. What is a Progressive Web Application? → A website that acts like a mobile app
27. How should an NestJS professional handle a situation outside their scope of competency? → Recognize limitations and refer to or consult with appropriate specialists
28. What is the purpose of regular risk reviews in NestJS practice? → To identify new risks, evaluate control effectiveness, and update mitigation strategies
29. What is the value of written documentation in NestJS professional communication? → It creates permanent records, ensures clarity, and provides legal protection
30. Which NestJS package provides first-class TypeORM integration? → @nestjs/typeorm