Chris Lattner, in a post to the Swift Evolution mailing list:
I’m happy to announce that Ted Kremenek will be taking over for me as “Project Lead” for the Swift project, managing the administrative and leadership responsibility for Swift.org. This recognizes the incredible effort he has already been putting into the project, and reflects a decision I’ve made to leave Apple later this month to pursue an opportunity in another space. This decision wasn’t made lightly, and I want you all to know that I’m still completely committed to Swift. I plan to remain an active member of the Swift Core Team, as well as a contributor to the swift-evolution mailing list.
That “other space” that Lattner alludes to is, according to Mark Gurman, a VP position at Tesla.
Also making news today is Daniel Gross’ announcement that he’s leaving Apple for Y Combinator. Gross directed many of Apple’s machine learning initiatives, while Lattner created Swift; these are two of the highest-profile initiatives within the company.
Update: Tesla confirms:
We would like to welcome Chris Lattner, who will join Tesla as our Vice President of Autopilot Software. […]
It must be a weird day at Apple for Project Titan team members.
Update: A fun thought experiment is to consider whether Tesla offered Lattner the position, or if Lattner sought it out.