I wanted to find a way to install ruby 2.0 on Ubuntu 12.04 via Chef, without going the rvm route, which is harder to automate. After several tries, I finally found a list of .deb packages which are necessary and sufficient as pre-requisites. Writing it down here for my future reference, and maybe it will prove useful to others out there.
I downloaded most of these packages from packages.ubuntu.com (if you google their names you'll find them), then I installed them via 'dpkg -i'. Here they are:
The actual ruby .deb package was built with fpm by my colleague Jeff Roberts courtesy of this blog post.