I have recently started working on a minimalistic webapp for management of (game)jams.
The idea is to have something where people can create Jams and then submissions and ratings can also be done. Jamgaroo itself wont host any files, but markdown can be used in the description of jams/series/submissions so that you can have images and links and such.
Not all features are implemented yet. You currently can create and edit jams and series, but no submissions or ratings. The Code is a bit messy, since i am figuring out how flask works on the way, but that will be addressed when all basic features are implemented.