The SemApps middleware rely entirely on Moleculer, a microservices framework for NodeJS. This framework is progressive in the sense that at first all services can be on the same computer, but if you need more power, you can move them to other servers without much changes. You thus have all the advantages of microservices (clear architecture, ease of horizontal scaling) without the difficulty of setting up such architecture.
Every building block of SemApps is a Moleculer service, this way you can compose the backend that you need, only including the standards that you need. Services are grouped by packages, which are usually named after a semantic web standard. Each package thus includes one or more services.
We recommend that you go through Moleculer documentation to have a good understanding of what is going on. After this, it should be easy to configure the services that you need.