faraday_pattern_example.rb

class YourThing
  def self.connection
    @connection ||= Faraday::Connection.new do |b|
      b.use Faraday::Request::UrlEncoded 
      # and all the rest
    end
  end
  
  def connection
    @connection ||= begin
      c = self.class.connection.dup
      c.params['user'] = 'something'
    end
  end
end