Microservice-Based Agile Architectures: An Opportunity for Specialized Niche Technologies

This work discusses lessons learned from the development of a medium-size peer-to-peer distributed software system centered around asynchronous computation and message-/stream-oriented communication. Albeit foreign to traditional high-integrity systems, these architectural characteristics are making rapid headway into large-scale mission-critical and business-critical software infrastructures, thus becoming candidate solutions for the design of reliable systems. We wanted our software architecture to be agile, that is, versatile, easy to evolve and modify, and resilient enough not to degrade across changes. To meet this goal, we adopted the microservices style, which afforded us the choice of best-of-breed technology to implement the individual system parts. Embracing heterogeneity while seeking agility however challenged our ability to design effective solutions for component coordination and interaction, as well as the goodness of fit of the used technologies for system integration and testing. Reflecting on our experience, we distill the lessons we learned in terms of architectural patterns, highlighting the pros and cons we saw in the microservices style and in our technologies selection.