Google is making a big change to company leadership. In a memo to staff posted on Thursday, Google CEO Sundar Pichai announced that Prabhakar Raghavan, the senior vice president in charge of search, ads, and other important segments, will now take on the role of chief technologist.

“Prabhakar has decided it’s time to make a big leap in his own career,” Pichai writes. “After 12 years leading teams across Google, he’ll return to his computer science roots and take on the role of Chief Technologist, Google. In this role, he’ll partner closely with me and Google leads to provide technical direction and leadership and grow our culture of tech excellence.”

Nick Fox, who was part of Raghavan’s leadership team, will replace Raghavan, leading Google’s Search, ads, geo, and commerce products. Fox has helped launch products like Google Fi and RCS messaging, according to Pichai.

Google is shuffling some of its other teams around as well. The division in charge of Google’s Gemini app, led by Sissie Hsaio, will join Google DeepMind under CEO Demis Hassabis. The Google Assistant team will also become part of Google’s platforms and devices team.