training-kernel

Cursor is open-sourcing Mixture-of-Kittens (MoK), a fused MoE training megakernel for NVIDIA NVL72 that runs up to 2.37x faster than the strongest public baselines.

Introduces Flash-MSA, the first performant open-source training kernels for MiniMax Sparse Attention on Hopper and Blackwell GPUs, enabling efficient million-token training.