Snapshot-based stub/mocking of APIs.
Best Tools For Service Virtualization
Browse 9 + Service Virtualization Tools

snapstubFree
Mock API by intercepting requests on the network level. Seamlessly reuse the same mock definition for testing, development, and debugging.
Mocks ServerFree
Node.js mock server running live, interactive mocks in place of real APIs

MountebankFree
Over the wire test doubles