RVM is a really cool tool that allows users to have multiple Ruby installs. I suggest using it as its very useful, just like having a package manager for Ruby versions. When I switched to rvm, I was having errors on my production server that some Rails commands like bundle couldn’t be found. Long story short, here’s a link to the solution:
In case the link is down, here’s a brief overview:
After installing RVM System Wide (you can find this easily in Google), add this to your default bash profiles:
[[ -s '/usr/local/bin/rvm' ]] && source '/usr/local/bin/rvm'
Then in Capistrano, you must add this in your deploy.rb:
set :rvm_ruby_string, ‘some-ruby’ # Defaults to ‘default’
Also, you MUST HAVE RVM ON YOUR LOCAL MACHINE!
EDIT: Just in case, you can also install the rvm gem using gem install rvm.