[pbowyer]

As I understand it App Store apps are 'sandboxed' - so is there any way to use this to create light, snapshottable containers isolated from the main filesystem?

I've been using Vagrant and Virtualbox, but the lack of speed is painful. And the overhead with a couple running at once.

It just strikes me as odd that Ruby has rbenv, Python has virtualenv - but there's nothing language agnostic and native to the Operating System, that I can use to try out new languages/tools, and nuke if all goes wrong without messing up my OS X filesystem (or versions of installed programs).