Andrej Karpathy, one of OpenAI's original co-founders and Tesla's former AI head, joins Anthropic; says: I plan to resume my work on…

Andrej Karpathy, one of the original 11 co-founders of OpenAI and former head of Tesla's AI division, has joined Anthropic—making it official in a post on X that sent ripples through the AI industry. He started this week on Anthropic's pre-training team, which handles the large-scale training runs responsible for giving Claude its core knowledge and capabilities.

Karpathy will build and lead a new group focused on using Claude itself to accelerate pre-training research—a role that sits squarely at the intersection of AI-assisted research and frontier model development. He'll report to Nick Joseph, Anthropic's head of pre-training and himself a former OpenAI alumnus.

Karpathy brings a résumé few in AI can match

The 39-year-old Slovak-Canadian researcher earned his PhD at Stanford under Fei-Fei Li and co-designed the university's first deep learning course. At Tesla, from 2017 to 2022, he led the computer vision team behind Autopilot—overseeing everything from in-house data labeling to neural network deployment on Tesla's custom inference chip. He returned to OpenAI from 2023 to 2024, where he built a team focused on midtraining and synthetic data generation, experience that maps almost directly onto his new role.

Since leaving OpenAI last year, Karpathy has been one of AI's most visible public educators—running a popular YouTube channel, posting technical explainers, and launching Eureka Labs, an AI-native school whose first product walks students through training their own AI system. He coined the term "vibe coding" along the way.

What this means for Anthropic's AI ambitions

The hire is a clear signal that Anthropic believes the path to staying competitive with OpenAI and Google runs through AI-assisted research—not just raw compute. Karpathy is one of the rare figures who can bridge theoretical LLM research with the messy practicalities of large-scale training.

"I think the next few years at the frontier of LLMs will be especially formative," Karpathy wrote. As for Eureka Labs and his education work: he says he remains passionate and plans to return to it—just not yet.