The React Compiler

Somewhere in your React app, a carefully memoized component is re-rendering on every keystroke anyway, and you'd never know it. That quiet inefficiency is exactly what Meta set out to fix with the React Compiler, a build-time tool that automatically handles memoization so developers never have to write useMemo, useCallback, or React.memo again.

The compiler analyzes your code's actual data flow, derives dependencies precisely, and generates its own lean caching mechanism, one far more efficient than layering hooks by hand. It's already running in production at Instagram and the Meta Quest Store, where Meta measured some interactions becoming more than two and a half times faster. Sanity reported a 20 to 30 percent reduction in render time. Wakelet saw real-world Web Vitals improve across the board.

Version 1.0 landed in October 2025. Expo now ships it enabled by default in new apps. For Vite and Next.js, it's a single config change.

There are limits: it won't touch class components, can't stabilize unstable third-party references, and does nothing for slow networks or oversized bundles. But for the problem it solves, it largely just works.