service that has not yet come up, AppSwitch blocks the call for a certain time waiting for the target service to become live. Since it is known that the target service is a part of the application and is expected to come up shortly, making the client block rather than returning an error such as <code>ECONNREFUSED</code> prevents the application from failing to start. If the service doesn’t come up within time, an error is returned to the application so that framework-level mechanisms like Kubernetes crash