23. Stewart Butterfield

Co-Founder & CEO, Slack

Age: 42 | First AppearanceAfter Stewart Butterfield sold Flickr, the photo-sharing startup he co-founded, to Yahoo for $35 million in 2005, he began assembling a team of programmers in Vancouver to develop a weird online multiplayer game called Glitch. Flickr had been a happy accident that grew out of his first attempt to develop such a game. As Glitch neared completion, it turned out that it was not the game itself but the tool the programmers created to communicate with each other that had great value.Slack is now valued at $2.8 billion, and Butterfield is a beacon in the burgeoning tech scene in this city. Born in a cabin in Lund, B.C., he taught himself to code growing up and then studied philosophy at the University of Victoria and at Cambridge. His sensibility is perhaps best captured in the resignation letter he sent Yahoo, which is legendary in tech circles: “I will be spending more time with my family, tending to my small but growing alpaca herd and of course getting back to working with tin, my first love.”

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