Born in Brooklyn, New York, on April 24, 1983, and raised in Columbia, Maryland, Alexis launched his first business soon after completing degrees in commerce and history at the University of Virginia. Ditching his plan to become a lawyer, he partnered with a friend, Steve Huffman, and pitched a mobile food-delivery app to the American startup accelerator Y Combinator in 2005.

YC rejected the concept but accepted Alexis and Huffman, agreeing to back their idea for a user-driven online media aggregator and discussion forum called Reddit; the following year, it was sold to publishing conglomerate Condé Nast for a sum that, according to a 2020 tweet from Alexis’s personal account, exceeded his parents’ lifetime earnings.