LlamaFactory

The default answer to 'how do I fine-tune model X': whatever the architecture (Llama, Qwen, Mistral, VLMs…), whatever the method (LoRA, QLoRA, DPO, PPO, full), one YAML config or the LlamaBoard GUI runs it — with the broadest model-coverage matrix in open source and academic citation weight behind it. If TRL is the library you code against, LlamaFactory is the trainer you configure. NOT for frontier-scale RL dataflows (verl/slime territory), and the kitchen-sink coverage means version bumps occasionally break niche model+method combos — pin versions for anything long-running.