Blog

Notes & writing

Thoughts on web development, engineering, and things I'm learning.

October 14, 2026 · 14 min read

Backend Latency Explained: p99, Tail Latency and Node.js

Why average response time lies, how p99 and tail latency really work, and how to measure and reduce backend API latency in Node.js and NestJS, with real benchmarks.

backendlatencyperformancenode.jsnestjsapi design

October 8, 2026 · 11 min read

Idempotent POST Endpoints in NestJS: Stop Charging Customers Twice

Retries are everywhere: flaky mobile networks, load balancers, impatient users. Here's how to build an idempotency-key interceptor in NestJS with Redis that handles replays, concurrent duplicates and failures properly.

nestjsbackendapi designredis