In a keynote speech at Rails World 2026 held on September 23, 2026, David Heinemeier Hansson (DHH), the creator of Ruby on Rails, revealed that 37signals, the company he leads, will no longer engage in manual code writing as a standard part of its operations.
Product LaunchesDavid Heinemeier Hansson37Signals
Rails Creator DHH Announces End of Manual Coding at 37signals, Shifting to AI Agents
This article is a translation. Read the Japanese original
DHH described this shift as "Pencils Down." This signifies a transition from the stage of providing detailed implementation instructions to a stage where problems and desired outcomes themselves are handed over to AI agents (AI that operates autonomously based on human instructions). He cited the release of Claude Opus 4.5 in November 2025 as a historical turning point in programming.
Regarding the future role of developers, DHH explained that the focus will shift from "writing the code itself" to "building and monitoring the mechanisms (machines) that generate code and the production lines that support them, as well as evaluating them." While 37signals has previously experienced issues with architectural flaws when relying solely on AI outputs, they now emphasize the importance of moving into the role of creating systems that ensure agents do not fail, especially given the emergence of more powerful models.
Furthermore, he noted that when development is predicated on agents, efficiency for AI becomes more important than ease of writing for humans. He also revealed plans to rewrite the backend of the email service "HEY" in Rust for its next version, suggesting a migration toward languages that are easier for agents to write.
Sources
- Rails作者DHH「Pencils Down、もう手でコードは書かない」 それでもソフトウェア開発の未来は明るい理由 （ITmedia AI+、2026-10-01）