React Native Workers

Real threads for React Native. Web Worker–style API, backed by a separate Hermes runtime on its own thread — with structured-clone messaging, timers, shared memory, and full native-module access.

Documentation · Quick start · API reference · Examples

React Native runs all your JavaScript on a single JS thread, and drives UI updates from it. A long parse, a big image filter, or a tight simulation loop blocks that thread — so it can't dispatch updates and your UI stalls.

This library gives you a real one:

import { Worker } from '@ammarahmed/react-native-workers';

const worker = new Worker({
  inline: `self.onmessage = (e) => self.postMessage({ doubled: e.data * 2 });`,
});

worker.onmessage = (e) => console.log(e.data); // { doubled: 42 }
worker.postMessage(21);

It's a headless React Native: no UI, but the same JavaScript engine, the same timers and Promises, and the same native modules you already use.

Why it's different

Install

npm install @ammarahmed/react-native-workers

Requires the New Architecture with Hermes (RN 0.81.4+, developed against 0.86).