@Razi Kheir The changes introduced by HTTP2 are mostly at a lower level than the API http4k provides. Message-wise HTTP2 is compatible with HTTP1, so in practice it means we should support whatever the underlying client/server backend supports. At the moment we don't have anything to express HTTP2-specific features (binary messages, multiplexing, server push etc).
Out of curiosity: what particular feature of HTTP2 are you interested in?