What problem does it solve? Aligning language models to human preferences with DPO requires maintaining a separate reference model, doubling memory and compute. SimPO removes the reference model entirely while outperforming DPO, but getting the hyperparameters (beta, gamma-beta ratio, learning rate) right is tricky and mistakes cause loss divergence or capability forgetting. ## Core Features & Use Cases - Reference-free preference training: Launch SimPO training runs on models like Mistral 7B and Llama 3 8B using accelerate and DeepSpeed ZeRO-3 configs. - Hyperparameter guidance: Model-size and task-specific recommendations for beta, gamma-beta ratio, learning rate, and SFT weight, including reasoning-intensive settings for math and code. - Dataset preparation: Preference data formats, quality filtering, deduplication, and mixing strategies for UltraFeedback, HH-RLHF, and custom datasets. - Use Case: Fine-tune Llama 3 8B Instruct on cleaned UltraFeedback preferences with beta 2.5 and a small SFT weight to improve alignment without losing instruction-following ability. ## Quick Start Ask the agent to set up a SimPO training run for Mistral 7B on the UltraFeedback dataset with the recommended default hyperparameters.