Every React developer eventually meets the same fork in the road. You write an event handler that reads state, pass it to a child or an effect, and now you must choose: leave it as a plain inline function and watch every render create a new reference — breaking React.memo, re-running effects, re-subscribing listeners — or wrap it in useCallback and start playing dependency-array whack-a-mole, where one forgotten dependency means the handler sees state from three renders ago.
That second failure mode has a name — the stale closure — and it's arguably the most common React bug in production code. The fix has a name too: useEvent, proposed in an official React RFC in 2022, and available today as useEvent in @reactuses/core. It gives you a function whose identity never changes across renders but whose body always sees the latest state and props. Both halves of the fork, no trade-off.
This post covers the API, the three-line implementation trick that makes it work, how it compares to useCallback and to React 19.2's built-in useEffectEvent, real patterns, and the one rule you must respect (don't call it during render). TypeScript-first.
The Problem in Thirty Seconds
Here's the bug factory. A chat component sends a heartbeat with the current draft text:
