Wang Yongjun worked on optimizing graph replay synchronization for the vllm-project/vllm-ascend repository, focusing on backend performance improvements using Python. He introduced a gating mechanism that limited synchronization to cases where the graph mode is set to FULL, effectively reducing unnecessary overhead and improving replay efficiency. His technical approach involved implementing selective synchronization logic, which enhanced both stability and predictability during mixed-mode operations. Wang validated his changes against the vLLM v0.13.0 baseline to ensure compatibility and minimal regression. His work demonstrated depth in backend development and performance optimization, resulting in clearer, more maintainable code around the synchronization path.