The diagram below depicts the maturity level of a "bounded context" (or self-contained component) in the Open edX platform.
The model begins with No Boundaries (Monolith), where we develop and execute inside a monolithic ball-of-mud and there are minimal to no boundaries. With maturity, we move towards having explicit Logical Boundaries, where we develop and maintain separate plugins, but still deployed with the monolith. Ideally, however, we want to have Physical Boundaries with self-contained and independently coded/deployed/executed microservices and microfrontends. The microfrontends would communicate via (REST) APIs to the microservices and interconnect via HTTP hyperlinks. The microservices would communicate via an event streaming pub/sub framework.
