Jamgaroo is a free and open source software for managing your gamejams.
What is this
Jamgaroo is a platform, where you can run and manage your gamejams. You can create jams, people then can submit games to your jam and later rate them. The idea is that only the relevant information regarding managing your jams and their submissions are held by jamgaroo. There is no file hosting of any kind for example, but you can use markdown in the descriptions of your jams/series/games to include images and links to other resources. Also this is not meant as a discussion platform, so there is no way to reply to comments on the ratings for example.
To create a jam, login and click on
create jam. Once the jam is created and its in the "coding" timeframe
people will be able to submit games to your jam. While the "rating" timeframe those submissions can be rated.
If your jam happens in a series of jams, like once a year, you can create a series to link your jams together.
The description text of your Jam/Game/Series can have markdown in it. If you dont know what markdown is, there are a lot of guides out there(This one for example). So for example, even though jamgaroo wont allow you to upload images, you can still include some in the description of your jam/series/game by adding
![Alt text](https://example.com/path/to/your/image.jpg "a title").