What subset of JSONAPI Ember data supports?

So far I have been using custom JSON api and it have been so painful that I have decided to rewrite the backend to deal with JSONAPI instead of my custom JSON. However, reading the jsonapi.org specs it seems there are a lot of things to implement but I read somewhere I don't remember that ember-data actually uses a subset of the specifications.

However I cannot find anywhere in documentation, guides and googling as to which specs actually ember data uses. I want only to implement that given my time constraint. I will appreciate if anyone help me on this