During the third day I tried to develop juicybar. Started by writing new backend class for dock applications (currently it isn't really a class, but eventually you'll be able to have your information bar using bare X, Qt or GTK+ — whatever you want). We did some bughunting with Wolfgang Jeltsch and Duncan Coutts, which showed what evil things can happen if you don't use threaded runtime. Later I hope to make separate post about the future of juicybar, its problems and features.
I had to leave early, about 4.30 pm, to go to Eindhoven (it's also a topic of another post).
I'd like to thank all the organizers — they did really a great (and huge) work. I was glad to meet all those nice people at hackathon (whose names we all know from haskell-cafe). And of course I'm looking forward to the next Hackathon :-)