Sustaining agility through architecture. Experiences from a joint research and development laboratory

This paper is an experience report of a long running Scrum project, conducted in a collaboration between industry and research, in a so called "Joint Research and Development Laboratory". Over time in the collaboration, we experienced a constant decrease in the pace of our development progress. Planning forward only within the limits of single sprints was the main reason for this. It resulted in a degenerating design and therefore a lack of flexibility that affected the agility of our project. Therefore, we introduced the concept of "epicarchitectures", an architecture design for a coherent group of user stories. Shifting the planning horizon further, across single sprints, helped us to create more stable and reusable concepts and to construct simpler, more elegant, and more maintainable solutions. We were able to significantly reduce the refactoring effort and increase the development speed, without significant overhead. With reporting on our experiences we hope to provide practically applicable guidance on how to integrate lightweight architecting in agile development processes, to sustain agility while creating high quality products.