FWIW: You don't have to follow any of the Relay spec to use Relay. Though you'll lose many of the benefits if you don't at least use globally unique 'id' fields

FWIW: You don't have to follow any of the Relay spec to use Relay. Though you'll lose many of the benefits if you don't at least use globally unique 'id' fields on each major type. Connections are optional, the node interface is optional.