Also curious about this. For reasons that our team was personally against, we had to devote some serious upfront development work to building an integration with a WordPress backend and the rest of our Ember front-end (which consumed, thankfully, a JSON-API spec backend). We wrote custom adapter and serialization layers for this, which was trivial; the only exceptions to the ease of writing such code was when the WordPress developers would return bizarre status codes or missed root objects or some other such nonsense.