I found this guide to get started. Luckily, I was already familiar with Perl's plenv setup, so this all looked very similar.
Although plenv wants you to run your shell as a login shell and modify .profile, rbenv doesn't seem to work that way. I needed to follow the instructions exactly, and only modify the .bashrc, and then change my shell to NOT be a login shell.
Install rbenvI used this guide: rbenv
This is used to provide rbenv the ability to install new versions of Ruby. I used this guide: ruby-build
I chose to install the latest: rbenv install 2.1.0
However, this produce an error:
The Ruby openssl extension was not compiled. Missing the OpenSSL lib?
So, first you need to install libssl-dev
sudo apt-get install libssl-dev
Set the default version to Ruby 2.1.0ruby env global 2.1.0
Ok, so now that this is all complete, I can now be confident about what Ruby version I'm working with.
Next up is bundler to manage the versions of gems I want to use.