Hi! Thanks to the sponsoring of the GNOME Foundation as well as the hosts (Betacowork) and volunteers organizing the Developer Experience Hackfest I had the privilege to attend it.
Putting the most important thing for you at the front: we have created a presentation templates repository at https://git.gnome.org/browse/presentation-templates,holding some GNOME/GUADEC branded presentation templates. We have seen several other repositories popping up on services like GitHub holding GNOME branded presentation templates and decided that having a “more official” repository might get people to move their templates into a central location so we have a single point where people wanting to do presentations or creating new templates can go to. (I have also filed bugs against existing repositories to move into the GNOME template repository. If no bug has popped up yet for yours, please also try to move your slides.)
Among those things I was happy to help Bastian bringing some movement into the developer.gnome.org discussion (including wasting a few hours on a hello world internationalizable flask application with documentation testing and generation) and enjoy Christian writing some pseudo code for a coala plugin that integrates deeply into GNOME Builder. The latter may well result in a GSoC project – one way or another we (the coala developers) see forward to the promised tutorials on plugins for builder.