What problem does it solve? Setting up reinforcement learning training for LLMs typically requires wiring together distributed training, inference, and weight synchronization infrastructure by hand. This Skill provides guidance for using torchforge, Meta's PyTorch-native RL library that separates algorithm logic from infrastructure so you can focus on reward functions and loss design. ## Core Features & Use Cases - GRPO and SFT Training Workflows: Step-by-step configuration and launch instructions for math reasoning training with group-relative advantages, including reward function definition and monitoring checklists. - Custom Loss Functions: Implement new RL algorithms (GRPO, DAPO, CISPO, GSPO, SAPO variants) as isolated PyTorch modules without touching distributed infrastructure. - Multi-GPU Scaling: Configure tensor parallelism and distributed services across GPUs or SLURM clusters using Monarch actors, TorchTitan FSDP training, and vLLM inference. - Use Case: Train Qwen2.5-7B on GSM8K with GRPO across 3 GPUs by writing a YAML config and a reward function, then launching with a single command. ## Quick Start Ask the assistant to set up a GRPO training run with torchforge for a math reasoning dataset on 3 GPUs, including the YAML config and reward function.