This spec is an attempt to push for a stable replacement of Ruby 1.8.x with 1.9.3+ on RHEL based systems. I have based it off of the work of FrameOS specs for Ruby 1.9.3 and Ruby Enterprise Edition.

yum install -y rpm-build rpmdevtools readline-devel ncurses-devel gdbm-devel tcl-devel openssl-devel db4-devel byacc libyaml-devel libffi-devel make
rpmdev-setuptree
cd ~/rpmbuild/SOURCES
RUBY_VER=ruby-1.9.3
RUBY_SUBVER=p545
wget http://ftp.ruby-lang.org/pub/ruby/1.9/${RUBY_VER}-${RUBY_SUBVER}.tar.gz
cd ~/rpmbuild/SPECS
wget https://raw.github.com/imeyer/${RUBY_VER}-rpm/master/ruby19.spec
rpmbuild -bb ruby19.spec
ARCH=`uname -m`
KERNEL_REL=`uname -r`
KERNEL_TMP=${KERNEL_REL%.$ARCH}
DISTRIB=${KERNEL_TMP##*.}
yum localinstall ~/rpmbuild/RPMS/${ARCH}/${RUBY_VER}${RUBY_SUBVER}-1.${DISTRIB}.${ARCH}.rpm

PROFIT!

If you are having trouble on the last line because of installed rubies, then run:

yum remove ruby-* puppet facter

If yum can't find libyaml, install the epel repo.

• Builds
• Installs
• Overwrites/upgrades your currently installed ruby package (DANGEROUS)

• Split packages into ruby-libs, ruby-devel, etc (looking for help here)
• Install alongside Ruby 1.8.x

• If you upgrade from an already installed 1.8.x, you will need to re-install all of your gems. If anyone has a decent way to do this programatically, i'll add it to the doc.

• EPEL Yum repository (for rpmdev-setuptree)

Tested working (as sane as I could test for) on:

• CentOS 5.x x86_64
• CentOS 6.3 (Final)

This is by no means, correct, or sane. Nor does it follow any sort of policy for packaging. I leave that to the people who are most familiar with such things, and will willingly accept patches that add those features.