http://lists.macosforge.org/pipermail/macruby-devel/2012-April/008702.html"I have been experimenting with different alternate memory models for
MacRuby on my spare time, and one of them seems to work well, modulo a
few leaks. It's similar to ARC in design (but it has a different
implementation). I have been working on a MacRuby app with friends
using the new code, so far so good. I will merge my branch with GitHub
as soon as it's stable, with a few other improvements. That should
happen before Mountain Lion ships, so no worries, we should be fine."