---
url: /reference/OutputOptions.externalLiveBindings.md
---
# externalLiveBindings

* **Type**: `boolean`
* **Optional**

Whether to generate code to support live bindings for [external](Interface.InputOptions.md#external) imports.

With the default value of `true`, Rolldown will generate code to support live bindings for external imports.

When set to `false`, Rolldown will assume that exports from external modules do not change. This will allow Rolldown to generate smaller code. Note that this can cause issues when there are circular dependencies involving an external dependency.

## Default

true

## Example

```js
// input
export { x } from 'external';
```

```js
// CJS output with externalLiveBindings: true
var external = require('external');

Object.defineProperty(exports, 'x', {
  enumerable: true,
  get: function () {
    return external.x;
  },
});
```

```js
// CJS output with externalLiveBindings: false
var external = require('external');

exports.x = external.x;
```