debug is a tiny JavaScript debugging utility that works in Node.js and web browsers.
The tool solves the problem of selectively enabling and disabling debug output across different parts of an application without modifying code. It works by exposing a function that takes a module name and returns a decorated console.error function. Developers toggle debug output using the DEBUG environment variable with space or comma-delimited namespace names, supporting wildcards and exclusion patterns. Each debug instance receives a generated color based on its namespace to aid visual parsing of output. The tool also displays millisecond differences between consecutive debug calls, showing elapsed time during development.
The tool suits developers who want lightweight, zero-configuration debugging without adding logging frameworks to their codebase. It works equally well in Node.js and browsers, making it useful for full-stack JavaScript projects. The namespace convention of using library names with colon-separated features allows multiple debuggers to coexist without naming conflicts. Developers should install the supports-color module alongside debug in Node.js to access the full color palette; without it, only basic colors are available. Browser support includes WebKit inspectors, Firefox, and Firebug, all of which understand the %c formatting option for styled console output.
The project maintains active engagement with its community through public funding mechanisms. Development shows consistent responsiveness to issues and pull requests, with maintainers actively reviewing and merging contributions. The codebase receives regular updates addressing edge cases and compatibility concerns across different environments. Documentation is thorough and includes platform-specific guidance for Windows command prompt and PowerShell users, reflecting attention to developer experience across operating systems.
