Executing component tests against a microservice deployed as a separate process allows more layers and integration points to be exercised. Since all interactions make use of real network calls, the deployment artifact can remain unchanged with no need for any test specific logic.

With this approach, the complexity is pushed into the test harness which is responsible for starting and stopping external stubs and coordinating network ports and configuration.

As a result of the network interactions and use of a real datastore, test execution time is likely to increase. However, if the microservice has complex integration, persistence or startup logic, the out-of-process approach may be more appropriate.