The fight between Apple and Tesla over engineering talent appears to be ongoing, with an announcement that Chris Lattner is leaving Apple to join Tesla, Engadget said. Lattner was the Senior Director and Architect at Apple, where he created the open-source Swift programming language. Beyond his work on Swift, which Apple introduced during its WWDC 2014 event, Lattner is also the author of LLVM. At Tesla, he will be leading the Autopilot team that continues to develop its driver assistance and self-driving technology.

The move is particularly notable not only because of Elon Musk's 2015 line that "If you don't make it at Tesla, you go work at Apple," but also those rumors about the direction of an autonomous car project within Apple, Engadget said.

News of Lattner's departure first surfaced via an email to the Swift Evolution mailing list, where he promised to "remain an active member of the Swift Core Team."