TurboModules & JSI: Future‑Proof Native Modules in React Native

Insight

TurboModules replace the classic bridge with a direct C++/JSI link, eliminating serialization costs and enabling synchronous calls from JavaScript. When you register a module as a TurboModule, the runtime loads it once and keeps a native pointer, so subsequent method calls are just function calls on the C++ side. This results in measurable latency drops, especially for high‑frequency APIs like sensor polling or crypto operations.

Example

// src/native/DeviceInfo.ts
import {TurboModuleRegistry} from 'react-native';

export interface DeviceInfoSpec {
  getBatteryLevel(): Promise<number>;
}

const DeviceInfo = TurboModuleRegistry.getEnforcing<DeviceInfoSpec>('DeviceInfo');
export default DeviceInfo;

The native side implements DeviceInfo as a C++ JSI module, exposing getBatteryLevel without any async bridge.

Takeaway

If you need low‑latency native calls, migrate performance‑critical modules to TurboModules/JSI. The migration is incremental—keep existing bridge modules and only rewrite the hot paths for a noticeable speed boost.