JavaScript
Why React re-renders: understanding the Fiber work loop
Most React performance problems are really scheduling problems. A practical look at Fiber, reconciliation, and what actually happens after setState.
Performance
JavaScript
Most JavaScript performance problems aren't JavaScript problems
After enough profiling sessions you start to realise the language is rarely the bottleneck. Our assumptions usually are.
Architecture
Caching is easy until it isn't
Most caching strategies look brilliant during architecture reviews and become considerably less impressive the first time stale data reaches production.
JavaScript
Why JavaScript performance is weird
Modern JavaScript engines are astonishingly fast, but only because they spend most of their time pretending your code is better than it actually is.
JavaScript
The event loop is not what you think
Most explanations stop at the call stack and callback queue. The reality is more interesting, and explains many of the bugs engineers encounter in production.