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+---
+title: Store Event Handlers in Refs
+impact: LOW
+impactDescription: stable subscriptions
+tags: advanced, hooks, refs, event-handlers, optimization
+---
+
+## Store Event Handlers in Refs
+
+Store callbacks in refs when used in effects that shouldn't re-subscribe on callback changes.
+
+**Incorrect (re-subscribes on every render):**
+
+```tsx
+function useWindowEvent(event: string, handler: (e) => void) {
+  useEffect(() => {
+    window.addEventListener(event, handler);
+    return () => window.removeEventListener(event, handler);
+  }, [event, handler]);
+}
+```
+
+**Correct (stable subscription):**
+
+```tsx
+function useWindowEvent(event: string, handler: (e) => void) {
+  const handlerRef = useRef(handler);
+  useEffect(() => {
+    handlerRef.current = handler;
+  }, [handler]);
+
+  useEffect(() => {
+    const listener = (e) => handlerRef.current(e);
+    window.addEventListener(event, listener);
+    return () => window.removeEventListener(event, listener);
+  }, [event]);
+}
+```
+
+**Alternative: use `useEffectEvent` if you're on latest React:**
+
+```tsx
+import { useEffectEvent } from "react";
+
+function useWindowEvent(event: string, handler: (e) => void) {
+  const onEvent = useEffectEvent(handler);
+
+  useEffect(() => {
+    window.addEventListener(event, onEvent);
+    return () => window.removeEventListener(event, onEvent);
+  }, [event]);
+}
+```
+
+`useEffectEvent` provides a cleaner API for the same pattern: it creates a stable function reference that always calls the latest version of the handler.