Rails comes with baked in support with bundler.

How to use Bundler with Rails

Install Rails as you normally would. Use sudo if you would normally use sudo to install gems.

$ gem install rails

We recommend using rvm for dependable Ruby installations, especially if you are switching between different versions of Ruby

Generate a Rails app as usual

$ rails new myapp
$ cd myapp

Run the server. Bundler is transparently managing your dependencies!

$ rails server

Add new dependencies to your Gemfile as you need them.

gem 'nokogiri'
gem 'geokit'

If you want a dependency to be loaded only in a certain Rails environment, place it in a group named after that Rails environment

group :test do
  gem 'rspec'
  gem 'faker'
end

You can place a dependency in multiple groups at once as well

group :development, :test do
  gem 'wirble'
  gem 'ruby-debug'
end

Learn More: Groups

After adding a dependency, if it is not yet installed, install it

$ bundle install

This will update all dependencies in your Gemfile to the latest versions that do not conflict with other dependencies