The React Compiler (formerly "React Forget") shipped stable in React 19. The promise? Automatic memoization — no more hand-crafting useMemo , useCallback , and React.memo wrappers. Just write plain React, and the compiler handles the rest.

But does it actually hold up? I ran a battery of benchmarks across real-world-ish scenarios to find out.

What the React Compiler Actually Does

Before we dive into numbers, a quick clarification. The React Compiler is a build-time Babel/SWC transform that analyzes your component tree and automatically inserts memoization where it's safe to do so.…