5 articles
Your API is running the same database query hundreds of times a minute. Redis caching fixes that — response times drop from 400ms to under 10ms. Here's the complete setup: client config, cache-aside pattern, per-user keys, cache invalidation, and a reusable Express middleware.
A slow MongoDB + Node.js API was taking 15 minutes to return 8,000 records. Here's the exact process I used to diagnose it — missing indexes, in-memory aggregation, no pagination — and bring it down to 15 seconds.
Every JavaScript developer has written await Promise.all(items.map(async item =>...)). It works — until you hit a rate-limited API, a paginated async generator, or a ReadableStream. Array.fromAsync() is the purpose-built replacement you didn't know you needed.
Your Node.js server runs fine for days. Then memory climbs past 800MB, then 1.2GB, then the process restarts. That's not a capacity problem — that's a memory leak. Here's how to find it before it finds you.
You open DevTools, check the console, inspect an element, close it. But DevTools is not a debugger — it's a full developer environment. Here's the power you're leaving on the table.
