Dark Peak is a user-run co-operative providing hosted open-source software for the benefit of our members. The 'co-op day' is when we get together to share knowledge, improve our services, and make decisions.
Non-members interested in learning more about the project are welcome to attend. If you're unable to make the event in person you can join us in #darkpeak on Freenode, where we'll post updates and be available to answer questions.
Doors open at 11:30am, official start time is 12:00pm. The event usually runs until people get hungry and we head out to find some dinner. Attendees are not expected to stay for the whole day, just drop in for however long you like.
If you'd like to ask questions before the event, the best place is on the mailing list (https://lists.richardskingdom.net/mailman/listinfo/sheffgeeks-hosting) - or in #darkpeak on Freenode IRC.