Can SOA and Microservices co-exist?

Question

It is often documented to build a microservice based architecture from a monolith. Is it also possible to have microservices in SOA based architecture?

Answer 1

Yes, you can absolutely have both architectures in the same environment. Here is why:

Microservices Architecture is heavily inspired by SOA, so naturally principles used in both are very similar and there's often confusion between both. However, you should note that these paradigms differ in scope. Microservices Architecture is an approach to design an application in a specific way, while SOA aims to put order in communication between multiple heterogeneous applications (often in enterprise environment) in different domains, avoid point-to-point communication by having a middleware in place and generally reduce integration effort and increase ROI in the long term. SOA is not just an architectural approach but offers a whole new approach to optimize the IT domain in an enterprise. It often requires changes to processes and hierarchy, because a SOA governance body would need to be in place at some point to ideally enforce enterprise policies.

So in practice you'll very often see something like this - many application architecture styles in the same general SOA:

Hope this helps.