Developers spend a surprising amount of time on repetitive tasks: checking project files, validating configurations, finding code issues, and debugging unexpected behavior. Small developer tools can automate these tasks, reduce mistakes, and make everyday workflows significantly faster.

JavaScript is an excellent language for building developer tools because Node.js provides direct access to the filesystem, process arguments, environment variables, and command-line output. You can build everything from simple code generators to sophisticated command-line interfaces without introducing another programming language.

In this tutorial, we will build a practical command-line code analyzer using Node.js.…