Worked on the inclusionAI/AReaL repository to deliver rollout versioning and trajectory logging enhancements, enabling per-sample version tracking and robust multi-turn trajectory analysis within the rollout workflow. Leveraged Python and data engineering skills to introduce run-length encoded version sequences and improve prompt and completion segmentation, ensuring accurate cross-turn analysis. Addressed issues with head_version and tail_version handling, as well as prompt_end calculation, to support reliable diagnostics and observability. Focused on backend development and thorough documentation, these changes enhanced the reliability and analytical depth of agent rollouts, supporting more precise performance evaluation and debugging for complex agent workflows.