Modern applications are highly distributed. We face challenges related to the use of internal and external APIs and how to build APIs with agility in the face of software that can evolve and change at any time. The API industry proposes two common strategies to circumvent these challenges: API Mocking and Service Virtualization. Both have pros and cons. At Cisco, we came up with the idea of API emulators has a third strategy to handle the challenges we were facing. As a result of our work, we published a reference implementation for Webex ChatBots. In this talk, we'll explain the motivation behind API emulators in the perspective of DevOps, CI/CD, Software Development, and serverless/microservices architectures. I will elaborate on the idea of integrating emulators as part of an overall API strategy, dive into the process of building such emulators, and validating them with Postman.