Rails engines are plugins to add functionality to multiples Rails apps.\

In this series, we're building https://animatedgif.me from scratch using Shrine. We'll start designing our database models, then get into designing our UI, writing tests and finally deploying our app to production.

Testing Ruby on Rails applications isn't hard, but you have to learn the basics well. We'll cover how to write unit tests, system tests, integration tests and more. We'll also explore mocks, stubs, factories, fixtures, minitest vs rspec and much more.