Ask HN: What (emerging) web standards are important for HTTP APIs in 2018?

I'm working on a HTTP API, and as much as high quality library code in Django Rest Framework has been able to shape the implementation, there are always questions and points of debate over things like error response shape.

Turns out, there's an RFC for that, RFC7807 describes the schema for a JSON problems/error object!

What are the important to follow RFCs and emerging web standards for HTTP APIs? How can I determine which of two possibly competing standards is more mature, e.g. rfc7396 & rfc6902 for JSON Patch...