Git for Windows - We bring the awesome Git SCM to Windows
rmtoo - rmtoo is a free and open source requirements management tool.
Mercurial SCM - Mercurial is a free, distributed source control management tool.
Doorstop - Requirements management using version control.
GitHub Desktop - GitHub Desktop is a seamless way to contribute to projects on GitHub and GitHub Enterprise.
Requirements Quality Suite - The Systems Engineering Suite offers you the tools, processes and skills to Verification, Traceability, Reusability and Quality.