An experience report on the adoption of microservices in three Brazilian government institutions.

Although monolithic applications are still the modus operandi of many software systems, the microservices architecture, which favors small and independent applications, is gaining increasing popularity. This is part due to its claimed benefits, which includes better scalability, productivity, and maintainability. However, little is known about how developers and architects perceive the benefits of migrating from monolithic applications to microservices, and what are the challenges towards achieving them. In this paper we discuss the motivation, benefits, and challenges related to the migration from monolithic enterprise architectures to a microservices based architecture. We report several lessons learned that arose from a two years process faced by three Brazilian Government Institutions. We also cross-validate these findings with a survey conducted with 13 practitioners in the studied companies. The results of our investigation highlight some evidence that the adoption of microservices brought several benefits for these institutions, such as (a) reducing development time and risks related to deployment activities and (b) increasing the opportunities to experiment with different technologies and development models (such as hackathons). However, our observations reveal that the adoption of microservices is still a challenging task, mainly because it not only demands the understanding of new techniques and tools, but it also increases the need to automate tasks related to software deployment and software monitoring. This study is particularly relevant for institutions interested in adopting a software architecture based on microservices, and we are currently sharing our experiences with other institutions.