Because who uses CVS anymore? Anyway, TkRev is a Tcl/Tk-based graphical interface to the CVS, Subversion and Git configuration management systems. It will also help with RCS.
It shows the status of the files in the current working directory, and has tools for tagging, merging, checking in/out, and other user operations. TkDiff is included for browsing and merging your changes.

TkRev also aids in browsing the repository. For Subversion, the repository tree is browsed like an ordinary file tree. For Git, the branches and tags are listed. For CVS, the CVSROOT/modules file is read. TkRev extends CVS with a method to produce a "user friendly" listing of modules by using special comments in the CVSROOT/modules file.

The user interface is consistent across Unix/Linux, Windows, and MacOS X.

TkRev is free and open-source.

Version 9.x:

• Added Git functionality!
• Speeded up branch browsing in Subversion substantially
• Updated tkdiff to version 4.3.5
• Made the Repository Browser more independent of the Working Directory Browser. You can now move around among repositories of different version control systems.
• Updated MacOS X UI to compatibility with version 11.1 (Big Sur)
• Many user interface tweaks:
  • Made a Copy/Paste right-mouse-button popup for the text widgets, so you can copy text from them
  • Re-arranged the Report and Status detail menus for more efficiency
• I'm no longer making stand-alone MacOS or Windows packages. But it will run on anything that Tcl/Tk 8.5 will run on.