karpathy/nanochat: The simplest experimental harness for training LLMs
Summary
nanochat is an experimental harness by Karpathy for training and interacting with small-scale LLMs on affordable hardware. It covers the full lifecycle from pretraining to evaluation and an interactive chat UI, emphasizes minimal, hackable code, and showcases cost-efficient training (GPT-2-grade models) with published speedrun benchmarks and scaling experiments.