NestJS · Junior · Question 8 of 75

Why does Nest use decorators like `@Controller()` and `@Injectable()`?

1They are required by Node.js for all classes
✓Correct answer: They attach metadata to classes and methods, which Nest reads to build routes and wire dependencies
3They make the code run faster

Explanation

Nest uses TypeScript's decorator support (experimentalDecorators) and emitDecoratorMetadata, which records constructor parameter types for DI.

Further reading

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