Okay, I can see it now, yeah. It should be in the relationships, but the issue is that we are currently requiring id, which doesn’t make sense in all contexts. I’ve just pushed something to main to make those optional. Additionally, extra attributes have to go in the "meta" key of the relationship, i.e {type: "type", "meta" => {foo: "bar"}}. This is required by the spec, IIRC.
