David Heinemeier Hansson (DHH), creator of Ruby on Rails and CTO of 37signals, describes how he went from publicly dismissing AI coding tools to going fully agent-first over a single winter break in late 2025. He explains how Claude Opus 4.5 was the inflection point that changed everything — producing code he actually wanted to merge — and how the shift feels less like being a project manager and more like stepping into a super mech suit.
DHH is the creator of Ruby on Rails, co-founder and CTO of 37signals (makers of Basecamp and HEY), and more recently the creator of Omarchy, a Linux distribution built on Arch and Hyperland. He switched to Linux two years ago and built Omarchy as a summer project during the 24 Hours of Le Mans downtime. In six months it attracted 400 contributors and tens of thousands of daily users — a pattern he's seen before with Rails and Kamal: scratch your own itch, and others like you show up.
37signals was founded in 1999, pivoted from a web design consultancy to a software company in 2004 after Basecamp took off. Current flagship products: Basecamp, HEY (email), and Fizzy. The team is ~60 people: ~20 programmers, ~10 designers, 14 customer support, and 10 in operations managing their own servers.
The signature pattern: start with a tiny team — often just one programmer and one or two designers — and only expand once the shape of the product is clear. "If you don't know what you want, a million people is not going to build it for you."
Designers at 37signals are not pixel pushers — they function as product managers, implementation leads, and aesthetic directors simultaneously. They define what to build, how it should work, and often implement the CSS/HTML/JavaScript themselves. DHH draws a parallel to jewelry design: you should know the properties of gold to design well with it. With agent acceleration, designers now prototype the entire thing end-to-end.
"Aesthetics is truth. When something is beautiful, it's likely to be correct. I think this is true in mathematics. This is true in physics. This is true in a lot of different domains."
DHH believes beautiful software and correct software are deeply linked. The obsession with aesthetics that extends from UI to code internals is what he looks for in engineers. Ruby in particular represents his aesthetic ideal — beautiful, flexible, non-dogmatic.
He cites the example of Apple: the loss of authentically native Mac applications represents an aesthetic failure that also correlates with a functional decline. Similarly, software built with genuine material understanding (working directly in CSS, HTML) naturally cuts with the grain of the web.
On the Lex Fridman podcast in mid-2025, DHH was dismissive of AI coding tools. His objections were specific:
The unlock came in two phases:
"I went from early November last year, I'm code first on everything... to now I start with the agent. Now he'll give me the draft. I'll review the draft and I'll make alterations if need be."
Daily setup (in tmux via Omarchy):
He starts every task in one of the agents, reviews the git diff (space gg in Neovim), and commits if it looks right. The ratio of "agent writes, DHH reviews/commits" versus "DHH writes directly" has inverted dramatically.
PR Review anecdote: Before releasing Omarchy 3.4, DHH faced 250 pending PRs. He gave Claude just the PR URL and asked for a review. Result: 100 PRs processed in 90 minutes. Breakdown:
"Claude's analysis of at least half the issues pertained to things I knew nothing about where it was undeniably a smarter, better reviewer, programmer than I could ever dream to be."
Autonomous agent test: DHH installed OpenClaw on a VM and told it to sign up for HEY and Fizzy with no tools, no MCP, no CLI. It autonomously navigated browser sign-up flows and completed both registrations. Then he invited it to Basecamp and it introduced itself to the team. Total time: ~7 minutes.
The biggest shift isn't doing existing work faster — it's doing work previously not contemplated:
The P1 Project: Jeremy (one of 37signals' most agent-accelerated developers) decided to optimize not P50/P95/P99 latency, but P1 — the fastest 1% of requests. He took floor latency from ~4ms to under 0.5ms, shipping 12 PRs over a couple of days as a "side gig" that would never have been scoped as real work before.
"The number of projects we have tackled internally that we would never even have contemplated starting on are legion."
DHH describes the feeling: like a king issuing vague commands and getting coherent analysis back. He's exploring adding dual-boot support to Omarchy — previously too risky and hairy to engage with — by having Opus and Codex ping-pong a plan back and forth before implementation.
This is the section with the sharpest edge. DHH's take:
Senior developers are the primary beneficiaries right now. They can validate agent output quality — the skill that made them senior is exactly the skill needed to supervise agents. They can work in parallel with multiple agents and 5-10x their individual productivity.
Junior developers face a more precarious position. They lack the architectural judgment to reliably validate agent-produced code for production systems. DHH references an Amazon internal analysis attributing major outages to junior developers shipping agent-generated code without adequate review.
"Junior programmers are not capable of figuring it out. Therefore, their role is suddenly more tenuous than it was 6-9 months ago."
Analogy: self-driving cars (FSD) improved dramatically over 18 months from "pretty good, pay attention" to "why is there a steering wheel?" DHH expects agents to follow a similar trajectory toward production-quality autonomous output — but the timing is unknown.
DHH argues we may have seen peak programmer — the era when being the implementation bottleneck commanded high compensation:
"I do actually think if I was going to bet we've seen peak programmer in terms of the learned guilt of programmers who went to either school or spent hours getting really good at it."
His nuances:
Shape Up methodology (37signals' 6-week cycles) is already becoming anachronistic — major features now ship much faster.
~100 programmers hired over 20 years from tens of thousands of applicants. Batting average: ~50/50 long-term success rate even after extensive vetting.
How to stand out:
"You're shooting your own feet if you show up at a shitty place and goof off. You know where that warm referral is going to come from? It's going to come from someone who identified that individual still showed up and did as best as they could."
The dopamine loop from shipping is dangerously intense right now. DHH's rules:
"Remember that this is as bad as AI's ever going to be. You damn well better find a way not to get consumed entirely by it."
A genuine, decades-old love of computers — since age 5. Whether it's video games, race cars (he races at Le Mans), or now orchestrating agents like a game of Starcraft, building is the mission itself, not a means to a financial end. He cites a hundred years of psychology showing that leisure without purpose is misery.
Looking ahead: CLI for Basecamp (nearly done), then HEY, Fizzy, and legacy products — making all 37signals tools agent-accessible. Leaning into what can be done today rather than trying to predict what AGI looks like in 18 months.
"Aesthetics is truth. When something is beautiful, it's likely to be correct."
"Running a bunch of agents feels less like being a project manager and more like stepping into this super mech suit where suddenly I don't just have two arms — I have 12."
"The number of projects we have tackled internally that we would never even have contemplated starting on are legion. The pie is just exploding right now."
"Claude's analysis pertained to things I knew nothing about where it was undeniably a smarter, better reviewer, programmer than I could ever dream to be."
"For you to get the privilege to just be an implementer, you have to be better than what's available off the shelf from agents."
"I'm enjoying my time as a programmer more than any time since the early 2000s when I just discovered Ruby. This has that 'I just discovered Ruby' feel to it."
| Time | Topic |
|---|---|
| 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 |