What problem does it solve? Aligning a base language model with human preferences requires navigating a complex post-training pipeline—supervised fine-tuning, reward modeling, and reinforcement learning—where misconfigured hyperparameters or memory limits frequently derail training runs. ## Core Features & Use Cases - Full RLHF Pipeline: Step-by-step checklists covering SFT, reward model training, and PPO optimization with working code for each stage. - Preference Alignment with DPO: Train directly on chosen/rejected pairs without a separate reward model, including beta tuning guidance. - Memory-Efficient Online RL: GRPO workflows with custom reward functions for GPU-constrained environments. - Use Case: You have a Qwen2.5-0.5B base model and a dataset of user preference pairs. Follow the DPO workflow to align the model, then evaluate it and merge LoRA adapters for deployment. ## Quick Start Fine-tune the Qwen2.5-0.5B model on my instruction dataset using TRL's SFTTrainer with LoRA and show me the training configuration.