AI Summary
5 min readDavid Heinemeier Hansson (DHH), creator of Ruby on Rails and co-founder of 37signals, spent last summer on Lex Fridman’s podcast bashing AI coding tools. Then, over the winter break, he did a 180. The trigger wasn’t a change in philosophy—it was that the tools finally got good enough. The combination of better models (Opus 4.5, which dropped in late November) and agent harnesses (like Claude Code and OpenCode) that let the AI use bash, call the internet, and write real code changed everything. DHH now starts every project agent-first, and says his enjoyment of programming is higher than at any point since he first discovered Ruby in the early 2000s.
The agent-first workflow
DHH’s daily routine has flipped. Before November, he would open his editor and code first, only asking an AI for help when stuck. Now he starts every task by telling an agent what he wants. He runs two models in parallel—Opus 4.5 in Claude Code and Kimi K2 in OpenCode—inside a TMUX layout on his Omachi Linux machine. The agent produces a draft. He reviews the diff in Neovim, commits if it looks right, or edits if it doesn’t. The ratio of agent-written to hand-written code has shifted dramatically in just a few months. He says the experience feels less like managing a project and more like stepping into a “super mech suit” where he suddenly has twelve arms and can look at seven screens at once. “I’m sti
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What you'll learn
- 1 (00:00) **Introduction: DHH’s 180 on AI** - The creator of Ruby on Rails and 37signals co-founder explains his shift from bashing AI coding tools to going AI-first over a winter break.
- 2 (01:17) **Building Omachi: Scratching Your Own Itch** - DHH describes creating a new Linux distribution as a personal project that resonated with thousands.
- 3 (03:08) **The Renaissance of Ruby on Rails** - Why Ruby and Rails are having a moment with AI agents.
- 4 (07:23) **37signals: From Consultancy to Product Company** - A brief history of the business and its major products.
- 5 (15:15) **The "Why" Behind Hey: Making Email Lovable Again** - The philosophy of the screener and reclaiming your inbox.
- 6 (17:32) **How Hey Was Actually Built** - The small-team, shape-up approach to taking on Gmail.
- 7 (27:10) **Aesthetics as Truth** - Why beautiful software is correct software and a source of happiness.
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Guests on this episode
Show Notes
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David Heinemeier Hansson (DHH) is the creator of Ruby on Rails and Omarchy, co-founder and CTO of 37signals (maker of Basecamp and HEY), and the author of several books including the best-seller, Remote: Office Not Required, co-written with Jason Fried.
Six months ago, in an episode of the Lex Fridman podcast, David shared how he doesn’t use AI tools to write code: he types out all his code. But things have changed a lot since then.
In this episode, we discuss his approach to building software, how it’s changed in the last six months, and why he now takes an agent-first approach, and how he barely writes any code by hand. We go into how he uses AI agents: which alter how he builds and explores ideas, but also how his standards of quality and craft remain the same.
We also discuss how 37signals thinks about product development, from the role of designers to the importance of aesthetics and taste. David gets into how he sees beauty and functionality as closely linked, and why strong opinions about design lead to better software.
Finally, we look into the uneven impact of AI which amplifies senior engineers while creating challenges for junior developers, and what this may mean for the role of the software engineer.
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Timestamps
(00:00) Intro
(02:11) Omarchy and Ruby on Rails
(08:25) 37signals overview
(10:12) Launching HEY
(18:38) Building HEY
(22:47) Designers at 37signals
(28:08) The craft of design
(31:52) Why DHH now embraces AI workflows
(39:45) The AI inflection point
(44:23) DHH’s agent-first workflow
(55:09) AI’s impact on junior developers
(1:03:08) Developer experience with AI
(1:16:43) What does AI mean for developers?
(1:23:33) 37signals teams and hiring
(1:38:20) Work-life balance with AI
(1:41:41) Why DHH keeps building
(1:45:24) Closing
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