VersionPress is a free and open-source plugin that brings the full power of Git to WordPress. Its key strength is that it version-controls not just files but also the database.
Key features include:
VersionPress automatically creates Git commits for both file and database changes, in natural language.
Plugins break, people make mistakes; sometimes, you just want that good old Undo button.
Git took the pain out of file merging; VersionPress does the same for WP database.
You can push to GitHub, your colleagues pull and make the site fully functional in seconds. MySQL is a cache.
VersionPress can store hundreds of full site snapshots to just a few megabytes.
We care about UX deeply. VersionPress should not be a low-level tool for geeks.