I decided to use "cgit" as a web interface to the git repository. Another option would have been "viewgit" and "gitweb" but I could not get either to work. Also cgit is pretty fast. Here is a mockup you can try. Let me know what you think.
Marc
Gambit Scheme system repository:
http://www.iro.umontreal.ca/~gambit/repo/.cgit.cgi/Gambit
Changelog:
http://www.iro.umontreal.ca/~gambit/repo/.cgit.cgi/Gambit/log