Vulcain

Vulcain is a protocol whose reference implementation is written in Go and that uses HTTP/2 Server Push to create fast and idiomatic client-driven REST APIs. It comes with an open source server gateway that you can put on top of any existing Web API to instantaneously turn it into a Vulcain-compatible API.

Vulcain supports not only hypermedia APIs, but also any “old” API by documenting its relations using OpenAPI.