RVM... Just Get Rid of It

17 February 2013

Gemset? Why should I compartamentalize my ruby dependencies if I am already using a Bundler? Isn’t that redundant? Yes, you are correct.

Recently, I have been configuring a Jenkins server to run our builds at work. We run a number of rails projects on the same ubuntu box, some on ruby 1.8.7 and some on 1.9.3. We run RVM and create a gemset for each project. RVM causes a number of issues when you are running bash scripts (jenkins runs each build using a shell script). Instead of whining about RVM, I much prefer to walk you through the process of replacing it with rbenv.

With proper bundler user, gemsets are unnessecary. Instead, define the gems required for a project in the project’s Gemfile. Then, run bundle install. rbenv is easily configured(see below!) to install gems to a projects’ vendor directory instead the default system gems.

Each application will be confined to only using gems defined in its Gemfile. However, please remember to refrain from installing gems with the gem install, except for global gems. The only gem that you should install manually is Bundler.

Replace RVM with rbenv

1. Uninstall RVM.
   rvm implode
gem uninstall rvm
2. Remove this line from your .bash_profile (or .zshrc)
   [[ -s "$HOME/.rvm/scripts/rvm" ]] && source "$HOME/.rvm/scripts/rvm"
3. Install rbenv & ruby-build(to install different ruby versions)
   brew update
brew install rbenv
brew install ruby-build
4. Install your favorite version of ruby. A few examples are provided
   rbenv install 1.9.3-p327
rbenv install 2.0.0-preview2
5. Rehash rbenv (do this after installing binaries)
6. Add these lines to ~/.bundle/config
   BUNDLE_PATH: vendor
BUNDLE_BIN: vendor/binstubs
BUNDLE_DISABLE_SHARED_GEMS: "1"
7. Add this line to your ~/.bashrc
PATH=vendor/binstubs:$PATH
8. Add these lines to your .bash_profile
   if [ -f ~/.bashrc ]; then
source ~/.bashrc
fi
9. source ~/.bash_profile
10. Enjoy life without gemsets!

Special thanks to Harry Marr for his directions that inspired this post.