A team built a million-line product using zero manual code, relying on Codex agents. Engineers steered prompts to achieve high throughput by designing agent-legible environments and feedback loops.
Highlights
Generated one million lines of code over five months using only Codex with no human-written code.
Small team achieved 3.5 pull requests per engineer daily by steering agents via prompts.
Success required agent-legible environments, structured knowledge, and progressive context disclosure.
Product shipped successfully and used by hundreds of internal users.
Engineers shifted focus to designing feedback loops and specifying intent rather than coding.