Andrew Lee focused on optimizing CI infrastructure for the DataDog/dd-trace-rb repository by migrating the continuous integration configuration to utilize new runner tags. This work involved updating YAML configuration files to align with the latest runner tag schema, which improved compatibility across different environments and reduced the occurrence of flaky builds. By standardizing the CI runner configurations, Andrew enhanced both the stability and maintainability of the pipeline, supporting upcoming updates to the CI runners. Leveraging skills in CI/CD, DevOps, and YAML, Andrew’s contribution addressed maintenance overhead and ensured the CI process remained robust and adaptable for future development needs.