#Performance

A practical guide to Core Web Vitals — what LCP, INP, and CLS measure, the thresholds Google uses, how to read field vs lab data, and a prioritized plan to fix each one.

A practical Postgres performance guide: read query plans with EXPLAIN, index the right columns, kill N+1 queries, and pool connections so the database scales.

Interaction to Next Paint replaced First Input Delay as a Core Web Vital. If your site felt fast in 2023 and 'got slow' since, INP is probably why — and the fix is mostly about your main thread.

Your production bundle is bigger than you think, and you probably can't name half of what's in it. Here's how to look inside and cut the weight that matters.

What the N+1 query problem is, why ORMs cause it by default, how to spot it, and the patterns that eliminate it for good.

Suspense lets React show fallback UI while a component waits, and streaming sends HTML in pieces. Together they kill the all-or-nothing loading spinner.

Scroll, resize, input, and mousemove fire faster than your code can keep up. Debounce and throttle are how you stop paying the event-loop tax — if you pick the right one.

On most pages the Largest Contentful Paint element is an image. Get that one image right and you fix the metric users feel most. Here's the playbook.

Most React memoization is cargo-culted and does nothing. Here's how to tell which re-renders cost you and where useMemo, useCallback, and memo earn their keep.

How Postgres index-only scans avoid touching the table heap, when they kick in, and how the visibility map quietly decides everything.

The React Compiler memoizes your components automatically. Here's what it does, what it doesn't, and which habits you can finally drop.

After profiling 50 production React apps, the same five problems showed up again and again. None of them were exotic — and all of them were fixable.

A practical mental model for how database indexes really work, why they speed up reads, and the hidden costs you pay on writes.

Autocomplete that stalls and red squiggles that lag are usually a type-checking problem. Here is how to find and fix the expensive types.