During October 2024, Seawardt focused on integrating Regression Test Selection (RTS) into the denoland/chromium_build repository, enhancing the build system to support more efficient test selection. He implemented Python tooling and updated GN build rules to reintroduce RTS, introducing a use_rts flag that conditionally generates dummy filter files to prevent test runner failures when RTS data is missing. This approach leveraged historical test data to optimize CI workflows and reduce unnecessary noise. Seawardt demonstrated depth in build system configuration, scripting, and test automation, delivering a targeted solution that improved the reliability and efficiency of the project’s testing infrastructure.