Andrej Karpathy started this week at Anthropic working on pre-training under team lead Nick Joseph, building a new team focused on using Claude to accelerate pre-training research itself. This represents a recursive bet on the most consequential problem in AI right now: using AI to make AI better.

The resume behind that announcement is unlike anyone else active in the field today. Karpathy was a founding member of OpenAI in 2016, Senior Director of AI at Tesla where he built Autopilot from scratch, and most recently ran Eureka Labs, his AI education startup. He also coined the term "vibe coding" in early 2025, a concept that spawned an entire ecosystem of tools.

CTOs of major companies have been quitting to take individual contributor roles at Anthropic. Workday, Instagram, Box, and You.com CTOs all stepped down from leadership to join as Members of Technical Staff. This talent flight coincides with Anthropic crossing $30B ARR in early 2026 and closing in on a $1 trillion valuation.

Pre-training is one of the most expensive, compute-intensive phases of building frontier models. Karpathy's work to apply AI to that foundational layer represents the kind of research that determines who wins the race to more capable systems.