Vertical Slicing: Smaller is Better

The technique of vertical slicing was introduced as a mechanism to combat our agile software development teams developing tendency toward building software in horizontal layers, building one service at a time, or grouping stories then breaking them down into layers. Those practices resulted in sprint reviews where no functionality could be demonstrated to the users and several iterations before all of the pieces were working together with useful functionality to show to users. Those habits continued when the next wave of projects with user interfaces came along. In this paper, we highlight the stories of four of our agile teams who tried vertical slicing, the challenges they faced, the victories, and the lessons learned.