In Rails you can replace the ActiveRecord layer using regular Rudy classes that include some ActiveModel modules. In this architecture, you’re using these clas

In Rails you can replace the ActiveRecord layer using regular Rudy classes that include some ActiveModel modules. In this architecture, you’re using these classes to replace models. Which gives you a layer of abstraction between the UI and the database. Querying becomes more difficult and some libraries won’t work out of the box, but it’s quite easy to implement. Most people don’t do this because this architecture isn’t the default, takes more time, and requires a larger application to justify doing a lot of work twice.