After twelve years this book is a little out of date. It mentions a few HTTP RFCs that never got approved (like Snell Link Methods datatracker.ietf.org/doc/draft-snell-link-method/) and there's no mention of newer techniques like GraphQL or tRPC.

It's still a pretty interesting read so far that still applies to the more abstract concepts in Hypermedia APIs. It would have gone over my head back in 2013, but I can grok it today after building apps on REST for all these years.