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Rails World 2026: DHH says hand-written code is obsolete

DHH says he wrote 150,000 lines of code in August 2026 alone, versus 30,000 a year by hand, as 37signals rewrites Hey's mail server in Rust.

By Tech AI Wire Team

3 min read

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A close portrait of David Heinemeier Hansson (DHH), wearing a gray hoodie, used as his official Rails World speaker photo.
Photo: Rails World

By the numbers

lines of code DHH says he wrote in August 2026 alone
150,000
less CPU use claimed for Hey's new Rust-based mail server
99%
time to install DHH's Omarchy Linux, down from 3 minutes 33 seconds a year ago
9s
pledged so far to the Omarchy Linux project, Dealroom reports
$20M

David Heinemeier Hansson, the creator of Ruby on Rails, told developers at this year's Rails World conference that writing code by hand no longer makes economic sense. According to a report from Dealroom on the keynote, he said he has "retired from being a professional programmer" and now calls himself a "maker" instead.

Hansson, widely known as DHH, argued that AI coding agents have made hand-typed code obsolete for most projects. He called it "the Kodak Brownie of our era," comparing hand-written code to an old, simple camera most people no longer need. "Agent-generated code is now the normal course of business," he said, according to Dealroom.

The numbers he shared back up the claim. DHH wrote about 150,000 lines of code in August 2026 alone, compared with roughly 30,000 lines a year in his old, hand-typed workflow, Dealroom reports. His own language mix has flipped too. Ruby now makes up about 3% of his output, down from around half over the past two decades, according to Jared Norman's analysis of the keynote.

The Hey rewrite

The clearest example is Hey, the email service built by Hansson's company 37signals. Hey is being rebuilt as six separate native apps, one for each platform, with a new mail server core written in Rust instead of Ruby. Dealroom reports the Rust rewrite cuts CPU use by 99% and memory use by 95% compared with the old server.

DHH has said before that Rust is hard for people to read. Norman's analysis quotes him calling the language "great for LLMs" even though it is "hideous" for humans, because AI agents, not people, now write and maintain most of that code.

Here is how the before-and-after numbers compare:

MetricBeforeNow
DHH's own code outputAbout 30,000 lines a year150,000 lines in August 2026
Hey mail server, CPU useBaseline99% less, Dealroom reports
Hey mail server, memory useBaseline95% less, Dealroom reports
Omarchy Linux install time3 minutes 33 seconds (Rails World 2025)9 seconds

Betting on agents, not just on Rails

DHH predicted that by the end of the year, "virtually all domains, virtually all programmers, virtually all companies" will use AI to generate code, Norman's analysis reports. He also said people reading code by hand should become "the exception, rather than the norm."

Dealroom also reports that DHH's Omarchy Linux distribution, a side project he maintains outside of Rails, has drawn about $20 million in pledged funding. Its install time dropped from 3 minutes 33 seconds a year ago to 9 seconds today. DHH pointed to that speedup as another example of what agent-written tooling can do. Separately, the Rails Foundation's own benchmark of coding agents found they completed 95% of test tasks correctly in an initial run, according to Dealroom.

Norman's piece argues the keynote said little about Rails' own roadmap, and that reaction from the Ruby community was largely negative. Some developers felt DHH used his opening slot to talk about AI and his own side projects instead, according to Norman.

What this means for developers

If you maintain a Rails app, nothing breaks today. DHH's claims are about how code gets written, not about Rails losing support. But the Hey rewrite is worth watching as a real test case. A well-known team is now betting that an AI-heavy, multi-language stack beats one shared Rails codebase, at least for their own product.

Be careful comparing your own output to DHH's 150,000-line month. That figure reportedly spans many small projects, not one finished application. Raw line counts are a weak way to measure working, shipped software.

Say you are choosing a language for a new backend service, and you expect AI agents to write most of the code. Weigh Rust's strict compiler checks against its reputation for being hard for humans to read by hand. Those checks catch memory and threading bugs before the program ever runs, which matters more when an agent, not a person, is doing most of the writing. Test that tradeoff on one small service before committing to a full rewrite.

Sources

  1. What About Rails? - Jared Norman
  2. Pencils down: DHH declares the end of hand-written code - Dealroom
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