Using instructions found http://robots.thoughtbot.com/using-rbenv-to-manage-rubies-and-gems and http://dan.carley.co/blog/2012/02/07/rbenv-and-bundler/. Here's how to get started with rbenv on OS X (assuming homebrew is installed):
brew update
brew install rbenv
Add the following lines to .bashrc:
# Homebrew rbenv
#To use Homebrew's directories rather than ~/.rbenv add to your profile:
export RBENV_ROOT=/usr/local/var/rbenv
if which rbenv > /dev/null; then eval "$(rbenv init -)"; fi
Restart the shell and install
brew install rbenv-gem-rehash
brew install ruby-build
Restart the shell and then install the rubies
rbenv install 2.1.3
rbenv global 2.1.3
Install rbenv-bundler
brew install rbenv-bundler
rbenv bundler on
Install bundler
gem update --system
gem install bundler
rbenv rehash
Configure bundler by adding the following to ~/.bundle/config
---
BUNDLE_PATH: vendor
BUNDLE_DISABLE_SHARED_GEMS: "1"
Finally, move into the root directory of the project and install gems
bundle install
rbenv rehash