[boomlinde]

IMO microservices from day one aren't necessarily a premature optimization, or an optimization at all. It is sometimes just the natural way to model a solution.

For example at my last job, we developed several services that constantly generated reports for our clients to run. Instead of embedding the functionality to move these files to other machines in each service, we developed a separate service that monitored a directory to do only that. This meant that the reporting services were more open ended: clients could decide how to handle the files but were still left with a very convenient option. It also meant that we could hand off new versions of the transfer service on its own for customers to install without interrupting reporting services, and only having to deal with the documentation of the transfer service itself.

In terms of scalability or performance, it added absolutely nothing, but it simplified deployment, documentation and development from day 1.