> For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt.

# output.externals

- **Type:**

```ts
type Externals =
  | string
  | object
  | function
  | RegExp
  | Array<string | object | function | RegExp>;
```

- **Default:** `undefined`

At build time, prevent some `import` dependencies from being packed into bundles in your code, and instead fetch them externally at runtime.

:::info
The usage of this configuration item is exactly the same as that of Rsbuild. For detailed information, please refer to [Rsbuild - output.externals](https://v2.rsbuild.dev/config/output/externals).
:::