debug

A tiny JavaScript debugging utility that uses environment variables to toggle granular log output without cluttering the console.

Debug provides a lightweight wrapper around console.log, allowing developers to instrument code with namespaced logging (e.g., 'http' or 'worker'). It boasts over 100 million weekly downloads on NPM because it solves the noise problem: logs remain dormant until activated via the DEBUG environment variable. The library handles color-coding for terminal readability and calculates millisecond deltas between calls to identify performance bottlenecks instantly. It is the industry standard for Node.js and browser-based diagnostics, used internally by foundational frameworks like Express and Koa.

https://github.com/debug-js/debug