During December 2025, contributed to the volcengine/verl repository by implementing support for the repetition_penalty parameter within RolloutConfig, addressing a common source of YAML configuration errors by introducing a safe default value of 1.0. This feature allows users to configure repetition_penalty during rollout processes while ensuring stability when the parameter is unspecified. The work involved backend development and API design using Python, with careful attention to configuration management. Comprehensive documentation and tests were provided to guide usage and maintain governance standards, and all changes were validated through pre-commit and CI checks to align with established pull request guidelines.