HF0, or Hacker Fellowship Zero, is a start-up accelerator that provides 12-week residencies for batches of fellows from 10 different start-ups. Their experience, which culminates in a demonstration day, is supposed to be the most productive three months of the fellows’ lives. Dave Fontenot, one of HF0’s founders, was inspired by the two years he spent living in monasteries in his 20s: While monastery life was materially ascetic, he found that it was luxurious in the freedom it gave residents to focus on the things that really mattered. And this year at the Archbishop’s Mansion in San Francisco, the home of the fellows, almost everyone has been monastically focused on what has become the city’s newest religion: artificial intelligence. The A.I. gospel had not yet spread in 2021, when Fontenot and his two co-founders, Emily Liu and Evan Stites-Clayton, started the accelerator. Even a year ago, when HF0 hosted a batch of fellows at a hotel in Miami, six out of the eight companies represented were cryptocurrency start-ups. But at the mansion in San Francisco, eight of the 10 companies in HF0’s first batch this year were working on A.I.-based apps. That generative A.I. has largely supplanted crypto in the eyes of founders and venture capitalists alike is not exactly surprising. When OpenAI released ChatGPT late last year, it set off a new craze at a time when the collapsing crypto and tech markets had left many investors and would-be entrepreneurs adrift, unsure of where to put their capital and time. Suddenly users everywhere were realizing that A.I. could now respond to verbal queries with a startling degree of humanlike fluency. “Large language models have been around for a long time, but their uses were limited,” said Robert Nishihara, a co-founder of Anyscale, a start-up for machine-learning infrastructure. “But there’s a threshold where they become dramatically more useful, and I think now it’s crossed that.”