It's a polyglot app server with microservice orchestration. It's definitely needed.
Some things to look for, such as registration/discovery of services, intra-cluster load balancing (where it started, no doubt), identity propagation & authn/z
The biggest issue to my mind though is distributed transactions and logging/debug/development. My biggest stumbling blocks with this sort of thing.. stepping through code over microservices is such a PITA.