Nscale, the buzzy U.K.-based AI data center startup, has appointed former OpenAI, Meta and Instacart executive Fidji Simo to its board.

Simo joins high-profile tech executives Sheryl Sandberg, Susan Decker and Nick Clegg on Nscale’s board ahead of the startup’s anticipated IPO this fall.

Formerly CEO of AGI Deployment at OpenAI, essentially the No. 2 executive at the AI lab, Simo left the company in July citing health reasons. She still advises the company on a part-time basis. Before OpenAI, Simo was chair and CEO of Instacart, where she led the company through its 2023 IPO. She also spent more than a decade at Meta, including as head of the Facebook app. Simo also sits on Shopify’s board.

Nscale’s founder and CEO, Josh Payne, said Simo is one of the few leaders who understand what it means to scale products used by billions of people and the demands those products place on the underlying systems.

“That’s what we’re building for at Nscale,” he said in a statement. “Fidji joins a board we’ve built deliberately, with the experience of scaling platforms to the largest in the world, and the independence, financial rigor and operating depth to which companies at this scale are held.”

Nscale’s valuation has skyrocketed since it was founded just two years ago on the back of booming demand for AI infrastructure. The startup, which designs, builds and operates AI data centers, is reportedly trying to raise up to $3.5 billion ahead of a planned IPO, Bloomberg reported last week, citing unnamed sources.