Blog

A Bloom filter's error rate is one of the few things we teach that you can actually check, so I built one, inserted 500,000 keys, queried it with ten million keys that were not in it, and compared the result against the textbook formula at seven different sizings.

Five runs of the same one-million-allocation loop on Node 22, changing only how many objects stay reachable, move total GC time from 13 ms to 334 ms — and that single fact explains most of what people get wrong about V8's heap, Go's missing generations, and why Twitch's 10 GiB of useless memory made their API faster.

Dijkstra's algorithm is four lines of greedy logic wrapped in machinery that fails quietly, so this post builds a binary-heap implementation in TypeScript, differential-tests it against Floyd-Warshall on 4,000 random graphs, and measures what the heap, the Array.shift() queue and the stale-entry check actually cost.

A measured tour of B-tree indexes on PostgreSQL 17, with real query plans for index-only scans, the visibility map, HOT updates, and the selectivity point where the planner abandons your index.

Awaiting four independent API calls in sequence instead of parallel can triple your endpoint latency. Here's the pattern, the math, and how to catch it in review.

You've read "Node.js is single-threaded and non-blocking." Fine. But that sentence raises more questions than it answers. If it's single-threaded, who's doing the file I/O while your JavaScript runs?

Your endpoint is async but it still freezes the server. Here's the synchronous CPU work pattern that blocks Node's event loop and how senior devs catch it in review.

You've run git commit thousands of times. But have you ever wondered what actually happens when you do? Git isn't a file-syncing tool with version numbers bolted on.

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.