DeepSeek-R1 ☆

R1 (January 20, 2025) matched o1-class reasoning and published how: large-scale reinforcement learning on verifiable rewards, with the R1-Zero ablation showing reasoning emerging from RL alone. Released MIT-licensed with distilled small variants, it topped app stores, triggered the January 27 market convulsion (NVIDIA −~17%, ~$589B in a day), and reset assumptions about the cost of frontier capability. Its paper later appeared on the cover of Nature.