Fundamentally, there isn't a huge difference between microservices and monotlic apps if both systems do the same thing. However, a lot of the issues of general

Fundamentally, there isn't a huge difference between microservices and monotlic apps if both systems do the same thing. However, a lot of the issues of general complexity are more apparent in one approach or the other. For example, breaking changes are breaking changes in either system. It's not an issue of architecture style, it's a matter of business needs changing, and thus protocols change. A change in protocol breaks the existing protocol. We understand this intuitively when you are talking about a de-facto protocol like HTTP, but we seem to think our own programs are somehow different. They aren't. Architecture is about taking the essential complexity of a problem and creating components and protocols to solve a problem in a way that makes the most sense for the team trying to solve it. Monolithic apps or microservices then should be a question more of what your team is going to execute well as much as it is a question of which structure more elegantly solves the problem at hand.