> ## Documentation Index
> Fetch the complete documentation index at: https://makeswift-docs-branch.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Upgrading to 0.21.0

If you haven't upgraded to `0.20.0` please read the [upgrading guide](/developer/upgrading/0.20.0).

`v0.21.0` of the runtime introduces some minor bug fixes/improvements, as well
as adding compatibility for Next.js 15 and React 19.

## Breaking Changes

### Pages Router's custom `Document`

If your site is using [Pages router](https://nextjs.org/docs/pages), the
Makeswift custom `Document` export has been moved from `@makeswift/runtime/next`
to `@makeswift/runtime/next/document`. To migrate, adjust the custom `Document`
import in `src/pages/_document.ts` as follows:

```diff theme={null}
- export { Document as default } from '@makeswift/runtime/next'
+ export { Document as default } from '@makeswift/runtime/next/document'
```

Here is the link to the [official release notes](https://github.com/makeswift/makeswift/releases/tag/%40makeswift%2Fruntime%400.21.0).