NestJS · Senior · Question 2 of 75

Why can a bundler or compiler without decorator metadata support break a Nest app?

1Nest needs the source maps
2Decorators are removed by Node.js
✓Correct answer: Without design:paramtypes, Nest can't resolve constructor dependencies by type, so injection fails unless every parameter uses @Inject(token)

Explanation

esbuild, for example, doesn't emit decorator metadata. SWC supports it with the right config, which is why Nest documents an SWC setup.

Further reading

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