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Type vs Interface

TH	when to use	limit	TH	TH
type	use it by default	no	TD	TD
interface	need to use extends; working with objects that inherit from each other;	can’t express unions, mapped types, or conditional type; Interfaces with the same name in the same scope merge their declarations, leading to unexpected bugs;	TD	TD

TypeScript performance wiki recommends using interfaces for object inheritance.

type WithId = {
  id: string;
};
 
type User = WithId & {
  name: string;
};

This is perfectly fine code, but it’s slightly less optimal. The reason is to do with the speed at which TypeScript can check your types.

When two interfaces with the same name are declared in the same scope, they merge their declarations

We could add ESLint to your project and turn on the no-redeclare rule.

nx:

  {
      files: ['*.ts', '*.tsx'],
      extends: ['plugin:@nx/typescript'],
      rules: {
        'no-redeclare': 'error',
      },
    },