I published the latest edition of the REST API Notes newsletter on 2017/05/17. Included is a great refresher on status codes by Mark Nottingham, a recorded video presentation on hypermedia and microservices for evolvable system design with Mike Amundsen, and just what next generation gateways like look like to Howard Dierking.
You can find the web version of the newsletter email here: http://tinyletter.com/NetAPINotes/letters/rest-api-notes-for-2017-05-17
Past editions of the newsletter can be found here: http://tinyletter.com/NetAPINotes/archive.
A comprehensive list of upcoming web events that I maintain can be found at webapi.events.