The whole thing started as a private indulgement for a space 'game' that I'll probably never release, but along the way I realized that the map bit was fairly standalone, so I decided to extract it and github it. There's still a ton of things I'm not satisfied with, but I don't know when I'll have the time or motivation to work on this again. Better to release something crap but working than nothing at all.
Things I want to fix: zoom should focus on mouse cursor, not corner of the canvas. Additional backgrounds for zoom levels larger than 1 are currently not working. For the game I'm hoping to fetch area data via ajax from the server but that's a whole other challenge. I also want to show sector contents such as star systems, starbases etc. Currently I've got a separate canvas library that does that, but I think I can integrate them.
More to come? Who knows. At least it's out there. If you fancy it, grab it, touch it, fork it, eat it. Technologic.