Simon Willison on Lenny's Podcast: 95% of Code Written from Phone, Mentally Exhausted by 11am

Simon Willison·medium signal

Simon Willison appeared on Lenny Rachitsky's podcast discussing the cognitive impact of coding agents, revealing he now writes 95% of his code from his phone and is mentally exhausted by 11am. He argues mid-career engineers — not juniors — are most at risk from AI displacement, and warns 'dark factories' (fully automated codebases) are coming. The episode marks a significant public statement from one of the most respected voices in developer tooling.