3i Member Spotlight

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

Episode Summary

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.

Episode Notes

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 investors
• The $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 does
• Why "good enough" isn't: why "move fast and break things" is the one startup mantra Fun can't afford to follow
• Where blockchain growth is heading: why 98% of Fun's business is already outside the U.S. and why Alex sees trillions moving on-chain

00:00 Welcome and introduction
01:27 The first company, built in middle school
03:22 Stanford, and deciding to leave
04:23 Who should go to college now
06:27 The problem: money sent into a black hole
07:14 Why value moves from databases to blockchains
09:01 What databases cannot do
11:37 A $400,000 transfer that arrived as $300,000
14:09 Mistake-proof rails, and why the biggest orders get the worst price
15:50 Why Fun stays invisible to the consumer
16:35 Why early startups have no moat
19:55 Talent density
21:13 Perfectionism, six nines, and Henry Ford
24:10 Rejecting work-life balance
25:29 The top priority: pull-based fiat rails
26:42 When the world hears about Fun
27:55 Ten years out
29:39 Reflecting on 3i