If the `@module-federation/modern-js` plug-in is used, the corresponding asynchronous entry will be enabled based on the builder type by default.

But if it is [build mode](https://modernjs.dev/en/guides/concept/entries.html#build-mode-entry), then you still need to set the asynchronous entry manually.

Next, we will demonstrate how to enable asynchronous entry.

Create the bootstrap.js file and copy the contents of the original entry file here:

```diff title="bootstrap.js"
+ import React from 'react';
+ import ReactDOM from 'react-dom';
+ import App from './App';
+ ReactDOM.render(<App />, document.getElementById('root'));
```

Modify the content of the original entry file and reference bootstrap.js instead:

```diff title="index.js"
+ import('./bootstrap');
- import React from 'react';
- import ReactDOM from 'react-dom';
- import App from './App';
- ReactDOM.render(<App />, document.getElementById('root'));
```