As backend developers, we often fly blind when building APIs locally. You write a route, but you don't really know how fast it runs until you leave your editor, set up Postman,
or configure a heavy APM tool.
I wanted performance testing to feel native and frictionless, so I built an open-source, zero-dependency local profiling extension for Node.js (Express & NestJS).
Here is what it brings directly to your editor:
🟢 Inline Latency Metrics: See real-time execution speeds (e.g., 🟢 84ms) rendered right beside your route definitions in the code.
🚀 1-Click Load Testing: A '▶ Load test' CodeLens sits directly above your route. Click it to replay the last recorded request 1,000 times under heavy load, simulating real
traffic instantly.
📊 Routes Dashboard: A dedicated VS Code sidebar showing all observed routes in your app, sorted from slowest to fastest.
🔐 100% Local & Secure: Everything is stored in local memory. No cloud accounts, no external dashboards, and no bloated tracking dependencies.
It takes less than a minute to set up—just install the lightweight middleware and the VS Code extension, and your editor comes alive with performance data.
I’d love for you to try it out on your local Express or NestJS projects! Let me know your thoughts, feature requests, or feedback in the comments.