Our Example Ruby App

The app we are building will let you input how much you earn as well as the city and country you’d like to move to. Then it will output a few living expense figures for that city.

Prerequisites

To follow along, ensure you have the following:

• Ruby development environment (at least version 3.0.0+) already set up.
• Bundler and Sinatra installed on your development environment. If you don’t have Sinatra, simply run gem install Sinatra.
• A free RapidAPI account since we’ll use one of their APIs for our app project.

You can also get the full code for the example app here.

Before proceeding with our build, let’s discuss something very important: the structure of Sinatra apps.