Controversial developer David Heinemeier Hansson (aka DHH) announced last week at Rails World 2026 that the end of handwritten code is upon us, calling it the modern era’s “Brownie” moment.

The moment to which he referred was when Kodak released its Brownie camera that forever changed the trajectory of photography. In this case, the Brownie of our era is AI.

During the event, DHH announced that his company, 37signals, decided it would no longer write code by hand and, instead, would use AI agents as its default code generation tool; humans were to only intervene when the auto-generated code needed to be fixed. To back up that migration, DHH proclaimed that he’d written half as much code over the past twenty months as he had in the previous twenty-one months.

One justification for this change, DHH addressed in a REWORK Podcast episode, when he spoke about how AI doesn’t suffer the same “attachment” to code as humans. To that, DHH said, “We are no longer attached to this piece of code that has been produced by prompts because I mean, we didn’t write it. There’s not a human on the other side. If you tell the AI to, well, you don’t tell the AI; you just start a new session and boom, amnesia. They’ve completely forgotten that they spent a lot of expensive tokens producing this stuff, and they’re not offended.”

During the Rails World 2026 keynote, DHH stated that at 37signals, “Writing code by hand is now an exceptional state.” He also did an informal poll of the audience, asking how many developers were still writing material amounts of code by hand. Only five people raised their hands.

Clearly, DHH is on to something.

During his keynote, he also brought up the lesson learned with Basecamp 5, when an early attempt at allowing designers to vibe-code a particular set of features left the architecture looking like “Swiss cheese.” The assumption was that the AI technology wasn’t ready for the task, so 37signals went back to manual coding. This experience led DHH to realize that there is only one serious question to ask: “How do you get the most out of this intelligence exposure?”

Now, 37signals is working on a new version of the email client, Hey, with the goal of it no longer being a web app. Prior to AI, creating web apps with small teams and the proper tooling, DHH claims, was the only way to be productive. He then went on to show a demo video of the new native Hey app looking very much as if it was production-ready, after only a few weeks of work.

This new version of Hey was vibe-coded, and the results (in his own words) were “electrifying.”

To DHH, using AI for coding is the future, and web apps would soon shift to native apps because of the efficiency of AI.

He also took a moment to display the first iteration of the Windows app that was vibe-coded, which was less than viable. After that moment, the audience got a peek at the next iteration of the app, which was created, with a few tweaks to the prompt, twenty minutes later. The results were astonishing.

To punctuate his point, DHH proclaimed, “This is coming. Get ready.”

The reactions to DHH’s keynote ranged from excitement about increased productivity to grief over the last craft of manual coding.