Simo's departure comes after transforming Instacart from a pandemic-boosted delivery service into a retail technology powerhouse with a profitable advertising business.

Instacart head Fidji Simo will step down to join OpenAI as its chief of applications, CEO and co-founder Sam Altman said on Thursday, adding she will report to him and that he will remain head of the Microsoft-backed ChatGPT maker.

Simo, already a board member at OpenAI, will transition out of Instacart over the next few months and join the AI company full-time as Application CEO.