Configurable provides a config method to store and retrieve configuration options as an OrderedHash.

Methods
C
Classes and Modules
Instance Public methods
config()

Reads and writes attributes from a configuration OrderedHash. 

  require 'active_support/configurable'

  class User
    include ActiveSupport::Configurable
  end

  user = User.new

  user.config.allowed_access = true
  user.config.level = 1

  user.config.allowed_access # => true
  user.config.level          # => 1

Source: show | on GitHub 

    # File activesupport/lib/active_support/configurable.rb, line 86
86:     def config
87:       @_config ||= self.class.config.inheritable_copy
88:     end