I looked through the DreamWidth source code to see if I could implement full-history syndication feeds for them, but they don't have things like querying for posts oldest-first, so it's more invasive than I feel like tackling right now.
Also it's in Perl which would be the fifth programming language I'd have worked on this stuff in over the last ~2 weeks, and the third one I've had to (re-)learn, and I'm getting kind of tired of switching languages this fast.