# initializeBlock

**Kind:** Function

`initializeBlock` takes the top-level React component in your tree and renders it. It is conceptually similar to `ReactDOM.render`, but takes care of some Extensions-specific things.

```js
import {initializeBlock} from '@airtable/blocks/interface/ui';
import React from 'react';

function App() {
    return (
        <div>Hello world 🚀</div>
    );
}

initializeBlock({interface: () => <App />});
```

**Parameters:**
- `entryPoints` (`EntryPoints`) — An object with an `interface` property which is a function that returns your React Node.

**Returns:** `void`