react-component-performance

npx skills add sickn33/agentic-awesome-skills --skill react-component-performance --agent claude-code

Same command for any agent — swap --agent for codex, cursor, copilot.

# React Component Performance ## Overview Identify render hotspots, isolate expensive updates, and apply targeted optimizations without changing UI behavior. ## When to Use - When the user asks to profile or improve a slow React component. - When you need to reduce re-renders, list lag, or expensive render work in React UI. ## Workflow 1. Reproduce or describe the slowdown. 2. Identify what triggers re-renders (state updates, props churn, effects). 3. Isolate fast-changing state from heavy subtrees. 4. Stabilize props and handlers; memoize where it pays off. 5. Reduce expensive work (computation, DOM size, list length). 6. **Validate**: open React DevTools Profiler → record the interaction → inspect the Flamegraph for components rendering longer than ~16 ms → compare against a pre-optimization baseline recording. ## Checklist - Measure: use React DevTools Profiler or log renders; capture baseline. - Find churn: identify state updated on a timer, scroll, input, or animation. - Split: move ticking state into a child; keep heavy lists static. - Memoize: wrap leaf rows with `memo` only when props are stable. - Stabilize props: use `useCallback`/`useMemo` for handlers and derived values