React Performance Engineering

Measure honestly

Use the profiler and field metrics to find the real bottleneck instead of the one you assumed.

Control re-renders

Understand why a component re-rendered and fix the cause rather than papering over it with memo.

Use concurrent features

Keep the interface responsive during expensive updates with transitions and deferred values.

Ship less JavaScript

Split, lazy load, and prefetch so the bundle stops being the first thing that hurts.