Payment Rails, First Principles, and the $100,000 Black Hole with Alex Fine of Fun

Our latest Member Spotlight podcast features Alex Fine, Founder and CEO of Fun (fun.xyz), the payments company building the deposit and withdrawal rails behind platforms such as Polymarket, Aave, and Lighter. Fun moves more than $18 billion annually for users in over 100 countries, following a recent $72 million Series A led by Multicoin Capital and SignalFire.In conversation with 3i Members Co-Founder and Chairman Mark Gerson, Alex traces his path from a Bay Area kid who idolized startup founders the way other kids idolized rappers or sports stars to building the infrastructure that quietly moves billions on-chain. He entered Stanford already planning to drop out and now focuses on solving one of crypto's biggest challenges: making blockchain payments reliable at scale.In this episode, Alex shares:The investor playbook: how first-principles thinking shapes his approach to building a business and his conversations with investorsThe $100,000 black hole: how a $400,000 transfer lost $100,000 in conversion and why solving that problem is at the core of what Fun doesWhy "good enough" isn't: why "move fast and break things" is the one startup mantra Fun can't afford to followWhere blockchain growth is heading: why 98% of Fun's business is already outside the U.S. and why Alex sees trillions moving on-chain00:00 Welcome and introduction01:27 The first company, built in middle school03:22 Stanford, and deciding to leave04:23 Who should go to college now06:27 The problem: money sent into a black hole07:14 Why value moves from databases to blockchains09:01 What databases cannot do11:37 A $400,000 transfer that arrived as $300,00014:09 Mistake-proof rails, and why the biggest orders get the worst price15:50 Why Fun stays invisible to the consumer16:35 Why early startups have no moat19:55 Talent density21:13 Perfectionism, six nines, and Henry Ford24:10 Rejecting work-life balance25:29 The top priority: pull-based fiat rails26:42 When the world hears about Fun27:55 Ten years out29:39 Reflecting on 3i