Context is the easiest way to share state, but also the easiest way to cause wasteful re-renders. Here are the five most effective selector patterns, ranked from simplest to most powerful.

Streaming SSR and traditional SSR both produce server-rendered HTML. The difference is in when the bytes arrive—and that timing gap matters more than most benchmarks show. Here is what changes in practice.

Inline functions and objects in JSX are convenient, but they create new references on every render. Here is what the profiler shows when you measure the cost.

A passing Lighthouse score today doesn't mean your app stays fast tomorrow. Here's how to catch performance regressions automatically, before they reach production.

Lazy loading with Intersection Observer is straightforward in theory, but several common implementation mistakes silently break it. Here is a symptom-based checklist to diagnose and fix them.

Infinite scroll in React consistently degrades performance when list items grow without bound. This post answers the real questions: intersection observers, virtualization, pagination internals, and strategies for browser memory throttling.

By the end of this guide you'll know how to eliminate loading spinners caused by late data or resource fetching, using techniques ranging from basic link hints to advanced route-level prefetching.

React 19 introduced several features marketed as performance wins. Testing shows some deliver measurable gains while others mostly simplify code. Here is the breakdown.

A step-by-step guide to using requestIdleCallback for deferring non-critical work in React, with code examples and measurement checkpoints.

By the end of this post you'll be able to define, enforce, and debug a performance budget for a React app — including the specific tools that catch violations before they ship.