React performance: slow apps, unnecessary re-renders, React.memo, PureComponent, code splitting, lazy loading, Suspense, virtualization, profiling, and bundle size
React apps become slow when they re-render too much, do expensive work in render, or ship more code and DOM than needed.
- Measure before optimizing
- Code splitting and virtualization reduce big costs
- Memoization helps only when it prevents meaningful work
React performance: slow apps, unnecessary re-renders, React.memo, PureComponent, code splitting, lazy loading, Suspense, virtualization, profiling, and bundle size