Installing Ruby on Mac OS X

The good news is you probably don’t have to. The following releases of Mac OS X already have ruby:

• Leopard ships with ruby 1.8.6 (2008-08-11 patchlevel 287)
• Snow Leopard ships with ruby 1.8.7 (2008-08-11 patchlevel 72)

Great! Don’t forget to update ruby gems:

sudo gem update —system

Assuming that you already have Ruby 1.8, the easiest way to install Ruby 1.9 and manage your versions is to use rvm: Ruby Version Manager