Ninja is a compact and efficient build system designed for fast incremental builds, particularly suitable for large projects with numerous files, such as Google Chrome and Android. Developed by Evan Martin of Google, Ninja stands out by rebuilding only modified components rather than the entire project, unlike traditional systems like Make. It requires a build file generated by tools like CMake or Meson, and its default settings promote parallel builds to enhance speed. While its primary advantage is speed, especially in incremental builds, it lacks the ability to function as a standalone tool without a build generator. The article provides a comprehensive guide on installing Ninja across various operating systems and demonstrates its use in creating and building both simple and incremental projects. Despite its limitations, Ninja is favored for its portability and minimal setup, particularly when integrated with existing build systems, offering significant time savings in development cycles.