> For the complete documentation index, see [llms.txt](https://overmindjs.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overmindjs.org/v23.1/api-1/createovermindssr.md).
# createOvermindSSR
The **createOvermindSSR** factory creates an instance of Overmind which can be used on the server with server side rendering. It allows you to change state and extract the mutations performed, which can then be rehydrated on the client.
{% tabs %}
{% tab title="server/routePosts.ts" %}
```typescript
import { createOvermindSSR } from 'overmind'
import { config } from '../client/overmind'
import db from './db'
export default async (req, res) => {
const overmind = createOvermindSSR(config)
overmind.state.currentPage = 'posts'
overmind.state.posts = await db.getPosts()
const html = renderToString(
// Whatever your view layer does to produce the HTML
)
res.send(`
${html}
`)
}
```
{% endtab %}
{% endtabs %}
## rehydrate
{% tabs %}
{% tab title="overmind/onInitialize.ts" %}
```typescript
import { OnInitialize, rehydrate } from 'overmind'
export const onInitialize: OnInitialize = ({ state }) => {
const mutations = window.__OVERMIND_MUTATIONS
rehydrate(state, mutations)
}
```
{% endtab %}
{% endtabs %}