Marissa Mayer

Marissa Mayer (born 1975) studied symbolic systems — an AI-adjacent degree — at Stanford before becoming Google’s twentieth employee and first female engineer in 1999, where she shaped the look of Google Search and ran products from Gmail to Maps. As Yahoo’s CEO from 2012 to 2017 she led one of tech’s most scrutinized turnaround attempts, ending with the company’s sale to Verizon.

Second act: an AI assistant called Dazzle

Her post-Yahoo startup, Sunshine (founded as Lumi Labs in 2018), spent six years on AI-flavored contact management and photo sharing without breaking through; Mayer conceded to TechCrunch that its problems were too “mundane” and that “I don’t think we got it to the state of overall polish and accessibility that I really wanted it to be.” In September 2025 she announced Sunshine would shut down and sell its assets to a new company she was forming.

That company, Dazzle, raised an $8 million seed round at a $35 million valuation in December 2025, led by Forerunner’s Kirsten Green with Kleiner Perkins, Greycroft and others participating. Dazzle is building a next-generation AI personal assistant — the team began prototyping it once foundation models became reliable enough to act on a user’s behalf, and Mayer said the project quickly eclipsed Sunshine in ambition, with potential for “a much bigger impact.” A launch was slated for early 2026.

Mayer’s arc is a distilled version of Silicon Valley’s: trained in AI before it worked, built the consumer internet, and returned to AI the moment the models caught up with the ambition. Whether Dazzle succeeds where Sunshine stalled is one of the more watchable founder comebacks in the field.