Usage

Running third party libraries in Worklets

Third party libraries have to be on an allow-list to use them in worklets. This is because libraries can come with side-effects that would break a Worklet Runtime. For instance, a library that imports something from React Native can't be used on a Worklet Runtime. This would load a second instance of React Native and break your app.

To add a library to the allow-list you only need to set importForwarding.moduleNames in the Worklets Babel plugin options. It's an array of library names. For instance, if you want to use my-library on a Worklet Runtime.

/** @type {import('react-native-worklets/plugin').PluginOptions} */
const workletsPluginOptions = {
  bundleMode: true,
  strictGlobal: true, // optional, but recommended
  importForwarding: { moduleNames: ['my-library'] },
};

The importForwarding API is temporary and will be replaced with a more robust solution in the future.

Running network requests in Worklets

In Bundle Mode, Worklet Runtimes come with a standalone networking module, no longer needing a feature flag. It's installed on every Worklet Runtime unless you opt out with enableNetworking: false.

const runtime = createWorkletRuntime({ name: 'worker' });

scheduleOnRuntime(runtime, async () => {
  'worklet';
  const response = await fetch('https://swmansion.com');
  console.log(response.status);
});

API	Supported
fetch, Headers, Request, Response	✅
XMLHttpRequest	✅
Blob, FileReader	✅
AbortController, AbortSignal	✅
FormData	String fields only, encoded as multipart/form-data.
Response streaming	❌
WebSocket	coming soon

Requests are made by the platform's own networking stack, they share the app's cookie storage and its TLS configuration.

Reference

To see how the setup looks in a real project, you can check out the Bundle Mode Showcase App repository.