The capital_one gem interfaces Ruby developers with the Capital One API. Simply require 'capital_one' and gain access to the API methods. Documentation for Capital One's API can be found at See lib/capital_one.rb for method definitions in Ruby.


Add this line to your application's Gemfile:

gem 'capital_one'

And then execute:

$ bundle

Or install it yourself as:

$ gem install capital_one


  1. Require the gem

    require 'capital_one'

  2. Go to and sign up for an API Key with your Github account. Read the documentation on the API and go to your Profile page and retrieve your API key. Once you retrive your key you must specify the key in your project to gain access to the API.

    Config.apiKey = "API_KEY"

    You will see that you are assigned two api keys when signing up for the API. These keys have different roles and permissions assigned to them.

    Enterprise Key - Take on the role of a Capital One employee. Only GET requests are permitted.
    Customer Key - Take on the role of a Capital One customer. All requests involving your assigned customers and anything they own are permitted.


After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to


  1. Fork it ([my-github-username]/capital_one/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request