Still working on it, continue tonight.
Topic on Talk:Amsterdam Hackathon 2013
It was left with various sections unreadable (black on grey). You may want to copy it to a sandbox next time (e.g. copy/paste to User:Henna/Amsterdam_Hackathon_2013 and then copy back once done).
I've polished it up a bit so that it is at least as readable as the old version.
Not only that, please also check the diff before saving, as you might be undoing legitimate edits (such as here, where typos and spacing issues previously fixed were reintroduced)
Visited links on dark gray are still unreadable, but maybe this only happens in the "See also" section?