Jenkins - Jenkins is an open-source continuous integration server with 300+ plugins to support all kinds of software development
GitHub Desktop - GitHub Desktop is a seamless way to contribute to projects on GitHub and GitHub Enterprise.
Buildbot - Python-based continuous integration testing framework
Git - Git is a free and open source version control system designed to handle everything from small to very large projects with speed and efficiency. It is easy to learn and lightweight with lighting fast performance that outclasses competitors.
Travis CI - Focus on writing code. Let Travis CI take care of running your tests and deploying your apps.
Mercurial SCM - Mercurial is a free, distributed source control management tool.