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

# source.decorators

- **Type:**

```ts
type Decorators = {
  version?: 'legacy' | '2022-03' | '2023-11';
};
```

Used to configure the decorators syntax.

## decorators.version

- **Type:** `'legacy' | '2022-03' | '2023-11'`
- **Default:** `'2023-11'`

Specify the decorator syntax version to be used.

In most cases, `2023-11` is the recommended choice:

- `2023-11`: the latest supported Stage 3 decorators proposal and the default used by Rsbuild.
- `2022-03`: the earlier Stage 3 proposal.
- `legacy`: the legacy Stage 1 proposal, mainly for projects that still rely on `experimentalDecorators`.

If you want to know the differences between different decorators versions, you can refer to: [How does this proposal compare to other versions of decorators?](https://github.com/tc39/proposal-decorators#how-does-this-proposal-compare-to-other-versions-of-decorators)

### 2023-11

`2023-11` corresponds to the November 2023 version of the Stage 3 decorator proposal.

```ts title="rsbuild.config.ts"
export default {
  source: {
    decorators: {
      version: '2023-11',
    },
  },
};
```

> References: [tc39/proposal-decorators](https://github.com/tc39/proposal-decorators), [@babel/plugin-proposal-decorators](https://babeljs.io/docs/babel-plugin-proposal-decorators).

### 2022-03

`2022-03` corresponds to the Stage 3 decorator proposal, equivalent to the decorator syntax supported by TypeScript 5.0 by default.

```ts title="rsbuild.config.ts"
export default {
  source: {
    decorators: {
      version: '2022-03',
    },
  },
};
```

> References: [JavaScript meta programming with the 2022-03 decorators API](https://2ality.com/2022/10/javascript-decorators.html), [TypeScript 5.0 Decorators](https://typescriptlang.org/docs/handbook/release-notes/typescript-5-0.html#decorators).

### legacy

Equivalent to TypeScript's `experimentalDecorators: true`.

This is based on the legacy Stage 1 decorators proposal. It will not receive new feature updates, and Babel and TypeScript may behave differently in some edge cases. It is recommended to migrate to `2023-11` when possible.

```ts title="rsbuild.config.ts"
export default {
  source: {
    decorators: {
      version: 'legacy',
    },
  },
};
```

> References: [A Complete Guide to TypeScript Decorators](https://mirone.me/a-complete-guide-to-typescript-decorator/), [TypeScript Decorators](https://typescriptlang.org/docs/handbook/decorators.html).

## Version history

| Version | Changes                                                                    |
| ------- | -------------------------------------------------------------------------- |
| v2.0.0  | Added `2023-11` version, default value changed from `2022-03` to `2023-11` |