  Development and Operations (DevOps), a particular type of Continuous Software
Engineering, has become a popular Software System Engineering paradigm.
Software architecture is critical in succeeding with DevOps. However, there is
little evidence-based knowledge of how software systems are architected in the
industry to enable and support DevOps. Since architectural decisions, along
with their rationales and implications, are very important in the architecting
process, we performed an industrial case study that has empirically identified
and synthesized the key architectural decisions considered essential to DevOps
transformation by two software development teams. Our study also reveals that
apart from the chosen architecture style, DevOps works best with modular
architectures. In addition, we found that the performance of the studied teams
can improve in DevOps if operations specialists are added to the teams to
perform the operations tasks that require advanced expertise. Finally,
investment in testing is inevitable for the teams if they want to release
software changes faster.
