> Has this been done already? I can think of a few things that are in the general area or cut across the problem you're solving here, but not anything exactly

> Has this been done already? I can think of a few things that are in the general area or cut across the problem you're solving here, but not anything exactly like it. Bundler and Isolate work at the level of single projects or applications, so that's not quite what you're doing here. Rvm provides gemsets, and the global gemset is closer to what Heist does. You can fill it with items that get installed automatically when you install any new Ruby interpreter. But I'm not sure that you can use it to automate installation of multiple versions of one gem (as you show with redis in your example). (You can also export and import gemsets which solves some of the pain you describe with moving from server A to server B.)