template = Slim::Template.new(
        Rails.root.join('app', 'views', 'user_mailer', 'send_registration_request.html.slim')
      ).render
      mg_client = ::Mailgun::Client.new(ENV['MAILGUN_API_KEY'])
      message_params = {
        from: '[email protected]',
        to: email,
        subject: 'The Ruby SDK is awesome!',
        text: template
      }
      mg_client.send_message(ENV['MAILGUN_DOMAIN'], message_params)