Do you need PHP 7.2 support in v2 of this library?
You seem to be using the new object typehint in some places, but I guess (hope) that's not life-critical. Is there anything else? Anything you wouldn't want to miss?

I am asking because we are considering using this library for Flarum (transitively through tobscure/json-api-server), and we want to keep supporting PHP 7.1 for a while.