Rumors have been rife for years that Apple has a secret car project in the works, and though the company has remained characteristically tight-lipped, the stories just won’t go away.

Now, though, Apple CEO Tim Cook has finally revealed that Apple is working on self-driving car tech – although he stopped short of confirming whether an actual vehicle is in the works.

Read more: still no Apple Car – so how could we build our own?

In a post-WWDC interview, Cook admitted that Apple is focused on “very important” core technology related to autonomous driving. Perfecting the driverless car is one of the biggest and most ambitious technical challenges in the world right now, and Cook believes the company is well placed to tackle it. With so much talk about “machine learning” at WWDC, perhaps we’ll see Apple enter the field earlier rather than later – especially if its contribution is mostly software-based.

What seems most likely at this point is that Apple will have a big hand in the underlying systems that power self-driving cars, but may team up with existing manufacturers rather than designing an entire automobile from scratch.

For more details on Apple’s self-driving car ambitions, check out this story over at MacWorld.