  The domain of cyber-physical systems (CPS) has recently seen strong growth,
e.g., due to the rise of the Internet of Things (IoT) in industrial domains,
commonly referred to as "Industry 4.0". However, CPS challenges like the strong
hardware focus can impact modern software development practices, especially in
the context of modernizing legacy systems. While microservices and DevOps have
been widely studied for enterprise applications, there is insufficient coverage
for the CPS domain. Our goal is therefore to analyze the peculiarities of such
systems regarding challenges and practices for using and migrating towards
microservices and DevOps. We conducted a rapid review based on 146 scientific
papers, and subsequently validated our findings in an interview-based case
study with 9 CPS professionals in different business units at Siemens AG. The
combined results picture the specifics of microservices and DevOps in the CPS
domain. While several differences were revealed that may require adapted
methods, many challenges and practices are shared with typical enterprise
applications. Our study supports CPS researchers and practitioners with a
summary of challenges, practices to address them, and research opportunities.
