DHH’s new way of writing code

Gergely Orosz, host of The Pragmatic Engineer podcast, interviews David Heinemeier Hansson (DHH), co-owner and CTO of 37signals and creator of Ruby on Rails, about an agent-first workflow that preserves a high bar for craft. DHH asks agents for drafts, reviews diffs, and uses senior judgment to decide what belongs; his productivity and labor-market claims remain personal observations and forecasts rather than controlled findings ([00:31:38]-[00:39:31], [01:03:21]-[01:07:21], [01:15:07]-[01:23:17]).

Key Points Covered

• The harness changed the interaction: DHH found autocomplete disruptive, while terminal agents could use tools and return complete drafts for deliberate review ([00:32:31]-[00:38:38]).
• Agent first still means human acceptance: He starts changes with an agent, inspects the diff, then commits, redirects, or edits according to the result ([00:44:19]-[00:48:32]).
• Models and harnesses are separate choices: DHH uses OpenCode as his main harness while comparing multiple models rather than treating one vendor's stack as indivisible ([00:45:22]-[00:47:28]).
• CLI composition expands useful scope: Small command-line tools let agents coordinate errors, pull requests, and project updates across systems ([00:48:32]-[00:52:18]).
• Senior judgment is the current leverage point: Architecture knowledge and review skill let experienced engineers redirect agents, but DHH does not argue that critical code is already safe without review ([00:54:25]-[00:57:18]).
• Craft standards still govern merges: Generated code must fit the project's aesthetics and conventions; faster output is not permission to keep work DHH considers sloppy ([00:38:38]-[00:39:31], [01:04:25]-[01:07:21]).
• Cheap drafts make more work economical: DHH describes trying speculative improvements and maintenance that previously would not justify the implementation cost, while supplying no controlled productivity measurement ([01:08:14]-[01:11:12]).
• Risky plans get independent critique: For dual boot, he had Opus and Codex challenge each other's plan before applying his own judgment; model agreement was an input, not proof of safety ([01:11:12]-[01:13:18]).
• Labor forecasts remain forecasts: DHH expects pressure on implementation-only work, but distinguishes 37signals' open-ended scope from cost centers and acknowledges uncertainty about timing ([01:15:07]-[01:23:17]).

Full video: https://www.youtube.com/watch?v=JiWgKRgdgpI(opens in a new tab)