Boxen is an open-source tool developed by GitHub to automate and manage Mac environments for its employees, streamlining the process of setting up development machines with a single command. Originally conceived as a project named "The Setup," Boxen allows new GitHub employees to begin working on GitHub's codebase within 30 minutes of unboxing a new laptop. It functions as a comprehensive framework utilizing a library of Puppet modules to manage services and applications, from MySQL to Minecraft, while incorporating continuous integration and automated issue tracking. Boxen is designed to accommodate teams similar to GitHub, featuring easy configuration through a recommended template for web development environments and the ability to roll out setups using a simple Rails app via boxen-web. The tool supports the addition of new services and tools through a Puppet module template, allowing teams to easily manage and run project dependencies. Contributions to Boxen from various GitHub departments ensure regular updates and improvements, reflecting its widespread use and the collaborative nature of its development.