A super small CLI program written with node that doesn't allow users with the wrong ruby (e.g. Windows users) see stuff
$ npm i -g nodejs-cli-wrongruby
Or check out this repository, run npm install and then npm link.
$ checkruby
Windows:
(Wrong Ruby) You are not allowed to see the nice stuff, sorry.
All other systems:
(Correct Ruby) Here is the nice stuff!
$ fakeruby
runs fake.js in the same repo - which is where I overwrite shelljs.which('ruby') to return the expected /usr/bin/ruby. All other parameters return their original value.