How do you compose multiple decorators into a single reusable decorator in NestJS?
Use applyDecorators() to bundle multiple decorators — including guards, metadata decorators, and Swagger decorators — into one named decorator. This reduces boilerplate on routes and co-locates all related concerns under a single, intention-revealing name like @Auth() or @ApiPaginatedResponse().
@Auth() composite decorator using applyDecorators
applyDecorators() design guidance:
Accepts any combination of method and class decorators.
Decorators are applied in the order listed — first in the array runs first.
Works for both method-level and class-level composition.
Ideal for bundling auth + Swagger + metadata decorators that always go together.
The composed decorator has a meaningful name — @Auth('admin') communicates intent better than 4 separate decorators.