Ex-Microsoft AI executive Peter Sellis takes over as X product chief: All details

Elon Musk’s X has hired Peter Sellis as head of product, succeeding Nikita Bier, who announced to step down after over a year in the role. Sellis is a known personality in the tech industry; he has served as Snapchat’s First Product Manager, Senior VP of Product at Discord, and as Corporate VP at Microsoft AI, among others.

Sellis shared an X post announcing the new role at the company. He laid out priorities to build on X’s recent momentum and make the platform more useful for existing users, new users, and businesses.

“X is the best way to find out what’s happening in the world right now and talk about it,” Sellis said. “My goal is to help accelerate that momentum for our community, new users, and businesses globally by continuing to make this product beautiful and useful.”

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With Sellis taking charge, X gains a product leader with experience in building consumer technology products. However, the company has yet to outline how his appointment could translate into changes for users.

Nikita Bier steps down

Nikita Bier announced to step down as Head of Product at X in August 2026. Bier joined the company in 2025, highlighting that his exit is in over a year. However, he plans to remain with the company temporarily as an advisor.

Musk also thanked Bier for his contribution, saying, “Thanks for helping make this platform much better! You will be missed.” Now, Sellis will be taking the reins, marking a major shift in leadership.

Who is Peter Sellis?

Sellis has established a strong reputation for leading product management across some of the world's most widely used digital communication networks. Before joining X as Head of Product, he served briefly as Corporate Vice President of Design, Engineering, and Growth at Microsoft AI.

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Between 2022 and 2026, he was Senior Vice President of Product, where he oversaw product strategy and steered major user growth cycles. Sellis worked at Snap (Snapchat) for over 7 years as the first product manager, leading The company’s first product manager, staying for 7 years (2015–2022). He stood up its monetization systems, leading the revenue product team from inception to a $4B+ business.

He also held executive and product roles at venture studio Science Inc., influencer network HelloSociety, and video streaming company Ustream.