DHH: ‘pencils down on hand-written code’ at 37signals
Partly confirmed
The takeaway
In his Rails World 2026 opening keynote (Austin, about Sept 23), Ruby on Rails creator David Heinemeier Hansson said 37signals is done writing code by hand: agent-generated code is now the default, and hand-written code is kept for fixing agent mistakes.
Status
- Claim
Partly confirmed
- Our reporting
- Medium confidence
- Importance
- 2 of 5
- Last verified
- 14 October 2026
Your AI and this story
- GPT-6 Astra146 days after its cutoff
- Claude Opus 5.585 days after its cutoff
- Gemini 4 Argon176 days after its cutoff
- Grok 4.7115 days after its cutoff
None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 85 days before it.
Key facts
- Claim: 37signals has stopped hand-writing code for professional work; agents generate nearly all of it (The Pragmatic Engineer, Sept 24; keynote summary)
- DHH dates the ‘age of agents’ to Nov 24, 2025 and says he wrote 150,000 lines of code in August 2026 alone, against about 30,000 lines a year before LLMs (keynote summary; Jared Norman’s critique quoted by SmartScope). These are his own figures
- HEY: being rebuilt as agent-written native apps, with the mail server core rewritten in Rust; slides claimed 99% less CPU and 95% less memory. DHH: ‘Hey is no longer gonna be a web app’
- DHH on Rust: ‘amazing if you never, ever, ever have to look at it yourself’ (Fireship clip)
- Audience poll: about five hands went up when he asked who still writes material amounts of code by hand, in a room of roughly 1,200 (Fireship; other write-ups say ‘only five’)
- DHH’s LinkedIn post: ‘it’s pencils down on hand-written code’; he called himself a retired ‘software writer’ and said the future belongs to ‘software makers’ (SmartScope)
- Fireship ‘DHH has gone completely off the rails...’ (Sept 28): ~2.24M YouTube views by Oct 11
- Date: SmartScope gives Sept 23; the recording summary is dated Sept 24 (UTC)
What happened
DHH, long a sceptic of hype around AI coding, used the Rails World 2026 keynote to say the switch is complete at his own company. Agents write the code; humans review and fix what the agents get wrong. He also argued that apps should ship command-line interfaces for agents, and that languages hard for humans to write, like Rust, become attractive when nobody has to read the code.
The keynote recording itself was not watched for this entry; details come from The Pragmatic Engineer’s open introduction, two written summaries and Fireship’s clips. Productivity numbers are DHH’s own and are disputed by critics.
Why it matters
A well-known framework author and former AI-coding sceptic declaring hand-written code over is a cultural marker of how far coding agents spread in 2026. It also shows a shift in how software is designed, towards agent-facing interfaces and code humans do not read.
Sources
4 sources from 4 sites. Numbers match the chips in the text.
4 sources: 1 press, 3 reactions
Press
- The Pragmatic Engineer: The Pulse, end of coding by hand? (Gergely Orosz, Sept 24)newsletter.pragmaticengineer.com, press
Reactions
- Dealroom: summary of the Rails World 2026 opening keynote (‘Pencils down’)dealroom.co, discussion
- SmartScope: Rails World 2026, DHH and the end of hand-written codesmartscope.blog, discussion
- Fireship (YouTube): DHH has gone completely off the rails...youtube.com, video
Changes
- Filed from lead (Fireship video, 2026-10-09)
