Rumors have been traded for years now about Apple’s automotive ambitions. Would Apple try to compete with Tesla to build an electric vehicle? Would it go toe-to-toe with its old foe Google to offer self-driving cars? In recent months, however, a clearer picture of Apple’s automotive work has slowly been revealed, most recently with Apple CEO Tim Cook telling Bloomberg in an interview that Apple is “focusing on autonomous systems. And um, clearly one purpose of autonomous systems is self-driving cars.”

Back in December, Apple wrote a letter to the National Highway Traffic Safety Administration (NHTSA) to say that it was investing heavily in machine learning and automation, without giving any salient details about what the company was building. Then in April, Apple applied for a California DMV permit to test autonomous systems on public roads using “three 2015 Lexus RX540h SUVs and six drivers.”

Cook’s recent comments are unsurprising but bolster the notion that Apple is working to build an autonomous car system, possibly one that extends beyond basic autonomous functions that have hit the road today. In Apple’s December NHTSA letter, the company’s director of product integrity Steve Kenner wrote, “Apple uses machine learning to make its products and services smarter, more intuitive, and more personal. The company is investing heavily in the study of machine learning and automation, and is excited about the potential of automated systems in many areas, including transportation."

Cook echoed that broad view of autonomy in his recent comments, too, noting that there are other uses for autonomous technology beyond transportation. He added, “we sort of see [autonomy] as the mother of all AI projects.”

But he ended on a vague note, saying, “We’re not really saying from a product point of view what we’ll do, but we are being straightforward that [autonomy is] a core technology.”

The Apple CEO also noted that the electrification of transportation as well as ride-sharing signaled a “major disruption looming.” Cook waxed especially effusive about electric cars as well. “If you’ve driven an all-electric car, it’s actually a marvelous experience. And it’s a marvelous experience not to stop at the filling station.”