Vercel React Best Practices

57 performance rules across 8 categories, prioritized by impact.

React Compiler (React 19+): If the React Compiler is enabled in your project, it automatically memoizes components, hooks return values, and expensive computations. Manual useMemo, useCallback, and React.memo are no longer needed in most cases — the compiler handles them. Rules marked ⚙️ below are automatically optimized by the compiler. Keep these rules as fallback guidance for projects without the compiler enabled.

useActionState (React 19+): For form submissions with server actions, prefer useActionState over manual useState + onSubmit handlers. It integrates with React's transition system and works with progressive enhancement.

Rule Categories by Priority