Chris developed a custom changed-files detection workflow for the semgrep/semgrep-rules repository, focusing on improving the reliability and maintainability of continuous integration. By replacing the external tj-actions/changed-files action with a Git-based approach, Chris enabled the CI pipeline to compute the merge-base with the develop branch and use git diff to enumerate changed files. This solution, implemented using Shell scripting and YAML within GitHub Actions, reduced external dependencies and provided finer control over pipeline execution. The work demonstrated a thoughtful approach to CI optimization, emphasizing deterministic change detection and clear documentation to support ongoing maintainability and traceability of the workflow.