The speaker says the official ARC-AGI-3 harnesses claimed to use or referenced Tufa or an abstraction inspired by it.

“the official one not not the like public prime and select one that or like what people have evaluated on they all like claim to use or they reference like like tufa for example some form or some inspired form of the arlen abstraction in their harness which is really really cool i think it's um this is where i mean this is exactly the setting where you would see a lot of benefits from composition and and using code and combining like neurosymbolic”