Every so often I like to completely wipe out my computer and start it over from scratch. This isn't because I particularly enjoy the pain of setting up a system from scratch, but it does come with some advantages. I took it upon myself to perform this task when I upgraded to OS X Lion and thought it would also be a great chance to write one of those "how to get a Ruby development machine going from scratch" posts since that's what I'd be doing anyway. So here's the process of how I got my machine set back up to work the way I want it to on Apple's latest.