Ruby 2.0.0 is here for quite a while. If you’re using RVM to manage your installed Ruby versions all you have to do is:

rvm install 2.0.0

If you haven’t updated RVM for a while, you’ll get the following error message:

Version '2.0.0' is to confusing to select ruby interpreter. Could not detect ruby version/name for installation, please be more specific.

To overcome this, just update your RVM with:

rvm get stable

And then you may:

rvm install 2.0.0

Welcome to Ruby 2! :)