Worked on improving build reliability for the facebook/buck2-prelude repository by addressing recurring failures in Remote Execution (RE) environments. Focused on stabilizing RE builds by modifying Starlark-based build rules to ensure that targets requiring the checkpolicy tool are evaluated locally, rather than remotely where the tool is unavailable. This was achieved by introducing a new label within genrule_local_labels.bzl, which directs the build system to handle checkpolicy dependencies appropriately. The change reduced RE-related build errors, resulting in more reliable CI runs and faster developer feedback. Demonstrated skills in build systems, CI/CD workflows, and Starlark for custom rule development and repository maintenance.