2026-05-19 · Express.js
Add rate limiting to an Express API
Pick a window strategy, key requests by user, and return 429s clients can actually handle.
Introduction
From installing a store to configuring proxies and Redis-backed limits, with sample responses and a stress-test check.
What usually goes wrong
Teams that skip this step tend to share three failure modes:
- Optimizing a number nobody agreed to move.
- Copying a setup from a project with different constraints.
- Deferring the decision until it is expensive to reverse.
How to approach it
- State the problem in one sentence, in the words your users would use.
- Pick a signal you can measure weekly, not just at launch.
- Timebox a small trial; a two-day spike beats a two-week debate.
Wrap-up
If Express.js taught us anything, it is that boring consistency beats clever one-offs. Bring the lessons back to your team before they fossilize into folklore.