Hoverfly allows developers to simulate APIs and test for latency and failures, ensuring interactions with other microservices don't change unexpectedly when code changes are made. Lyft Envoy and Ambassador provide an API gateway that exposes microservices easily, allowing for the monitoring of traffic and messages in production. Telepresence enables developers to swap out running code on a staging cluster with code running on their laptop, facilitating manual testing and debugging in a realistic environment.