I had much more trouble with this install than I did for Ubuntu, probably because I was trying to do more.

I started by trying to get packages with yum.
yum install ruby irb ruby-devel

That lead to a dependancy issue. I needed apxs, but what package is it in? Ended up being in the httpd-devel package.

Then I moved on to installing mod_ruby. Having the ruby interpreter run inside Apache seems like a good idea – at least from a performance standpoint. Here’s the guide I worked from.
http://www.modruby.net/en/doc/?InstallGuide

However, it turns out that mod_ruby comes with a slew of namespace complications. From the rails wiki, “considered unsafe to use mod_ruby and Rails with more than one application.”

FastCGI is a safer alternative. The rails wiki has good setup documentation:

http://wiki.rubyonrails.com/rails/show/RailsOnFedora

I did run into trouble with MySQL – I needed to tell Rails where the mysql.sock file was. Here’s a ticket explaining the problem.
http://dev.rubyonrails.com/ticket/200