We have built an example using Ruby 3.0.0 and Ruby on Rails 6.1.4.1, and the Vonage Voice API to create a simple Interactive Voice Response (IVR) service that accepts numeric input from callers and speaks back the input entered by the caller. To do this, we created a new Rails application, defined routes for two Controller actions (`answer` and `event`) that use Nexmo Call Control Objects (NCCO), configured ngrok to make our local development server externally accessible, set up a Vonage account, purchased a Vonage provisioned phone number, linked it to the application, and configured the Vonage application to accept phone calls and send them to the IVR Rails app. The application now provides a fully functional simple IVR service that can be tested by giving it a call at the purchased phone number.