Sanne Grinovero Sure, I don't want to break things randomly just to make them pretty. I'm suggesting this because QueryDescriptor only appeared in 5.6, which is still in beta. And because the change would more likely be a signature change than a paradigm shift.
Note that the Infinispan team seems to be trying to use the new SPIs right now (and having some issues), so on their side it might not be too late.

I'll try to propose something anyway if there's a quick solution, we'll see if it's worth the SPI break.