The following rules apply to all software projects that are hosted on gnome.org infrastructure:
The project must be free/open source software.
It must use GTK/GNOME technologies.
It must be maintained, and already have had at least one public release.
To the best of your knowledge, it must not infringe on patents (most gnome.org servers are in the US).
If copyright assignment is required, please read the GNOME policy on copyright assignments. (However, it’s simpler to not have any copyright assignment.)