Simon Willison’s Weblog

nanoGPT. “The simplest, fastest repository for training/finetuning medium-sized GPTs”—by Andrej Karpathy, in about 600 lines of Python.

Posted 2nd January 2023 at 11:27 pm

Recent articles

Embracing the parallel coding agent lifestyle - 5th October 2025
Designing agentic loops - 30th September 2025
Claude Sonnet 4.5 is probably the "best coding model in the world" (at least for now) - 29th September 2025

python 1190 ai 1599 gpt-3 67 andrej-karpathy 31 generative-ai 1408 llms 1378

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