SDPO (Self-Distilled Policy Optimization) is a framework for training large language models using reinforcement learning algorithms, built upon the verl (Volcano Engine Reinforcement Learning) foundation. The system provides a modular architecture for implementing PPO, GRPO, SDPO, and other RL algorithms with distributed training capabilities via Ray. It integrates with inference engines like vLLM and SGLang, supports multiple model architectures (Llama, Qwen with Megatron optimization), and includes reward modeling for domains like mathematics and coding. The framework features extensible components for reward managers, tools, and agent interactions, with experimental capabilities for fully asynchronous training and multi-turn reasoning. While actively maintained, the system's complexity and extensive dependency ecosystem present moderate technical drift risks.