Blog

The naive 10-line debounce works for demos. Build the real thing: leading edges, trailing calls, cancel, flush, and a throttle that never silently drops the last event.

Call fib(45) naively and JavaScript will make over a billion recursive calls. Call it twice and you double that. Your CPU fan kicks on, the browser tab freezes, and the function you thought was fast becomes your performance bottleneck.

Picture this: a live dashboard that polls for new notifications every 3 seconds. The count increments in state, the UI updates, everything looks right — except the interval callback is silently reading count = 0 on every tick, because it.

Docker containers aren't tiny VMs. They're Linux processes wrapped in namespaces, cgroups, and OverlayFS — here's how the kernel primitives actually fit together.

One binary and one config against six packages and a decade of plugins. The gap is real but narrower than the write-ups claim — Biome has had React Hooks rules since v1.0.0, and its v2 config drops the field most tutorials still tell you to set.

Lodash's curry is 10 lines. Build curry, partial, compose, and pipe from scratch in JavaScript — then use them to write clean data pipelines without a single nested callback.

Open a modal 10 times without cleanup and you've got 10 stacked timers silently draining memory. Here's what this looks like in a PR and how senior devs catch it.

Express has the ecosystem, Fastify has the schema validation, and Hono runs everywhere. Here's the practical breakdown of all three so you can actually make the call.

PostgreSQL trades storage space for concurrency — MVCC, WAL, and vacuum aren't quirks, they're the design. Understanding this explains most performance mysteries.