At Flatiron School, we use a project, playlister-rb, to move between the different layers of a web application and abstractions. First, we build a domain model that passes a test suite. Then we wrap a CLI application around that domain. Then we use ERB to generate a static version of a website. Then we implement a RACK layer to make a dynamic application. Then we implement Sinatra. Moving between these layers show interface independence of our models and the importance of a strong domain model. At this meetup, Avi Flombaum will walk through the various abstraction layers and demonstrate how powerful a well designed, interface independent, domain model is for application development.