Microservice is the modern and hot trending architectural design pattern now, ServiceStack should has builtin feature to support building microservice. In Java world they have Spring Boot / Spring Cloud to wire together other open source technologies such as Nextflix Ribbon, Eureka, Kafka etc. to build microservice.

Basically, ServiceStack should be identified itself to be not only a framework of choice to build not only RESTful webservice but also a full-fledged platform such as the Java's Spring framework