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

# server.rsc

- **Type:** `boolean`
- **Default:** `false`

Configure React Server Components (RSC).

:::warning UltraModern availability
RSC is experimental, default-off, and unsupported for external consumers; it is not shipped in the current UltraModern company distribution. Release-cohort and clean-room release-acceptance tests verify that RSC runtimes are absent and cannot resolve, and the release cohort has no maintained `@bleedingdev/*` RSC runtime package; when enabled, the framework intentionally fails closed unless an application supplies the complete optional toolchain.

The root-only `react-server-dom-rspack@0.0.3` patch backports Flight decoder security fixes for this repository's RSC tests; it is never copied into generated workspaces or published to consumers, so an app installing the upstream package receives unpatched bytes. [SyMind/react#1](https://github.com/SyMind/react/pull/1) merged on 2026-08-11; [BleedingDev/react#1](https://github.com/BleedingDev/react/pull/1) and [rspack#15144](https://github.com/web-infra-dev/rspack/issues/15144) remain open. npm still reports `react-server-dom-rspack` `latest` as `0.0.3`, with no patched consumer release, so the root-only patch remains necessary for this repository's RSC tests. This boundary is pending final owner ratification.
:::

```ts title="modern.config.ts"
export default defineConfig({
  server: {
    rsc: false,
  },
});
```

The [React Server Components guide](/guides/basic-features/render/rsc.md) is retained as reference material for future upstream adoption.