ikiwiki seems nice. It is git-based, so distributed, so you can defer the question of where it gets hosted. Also you can maintain it alongside and using the same tools as the code (it does allow web edits also). It is perl but supports plugins in any language. You could get a wiki up now, write plugins in arc, and do an arc rewrite in due course.
I'm a little sad that my newbie's intuition of how to get rid of boilerplate with functions/macros thoroughly failed, but this is educational. I will meditate on this some more and study those excellent docs. Thanks very much.
