Worked on enhancing the reliability of signal handling in the symfony/console repository by addressing a bug in the mapping of SIGSYS signals. Focused on improving correctness and test coverage, the developer refactored the SignalMap to exclude SIGBABY from the SIGSYS mapping, preventing potential misinterpretation of signals in production environments. The solution included implementing a targeted unit test to validate the new mapping and ensure future regressions are caught early. Utilizing PHP and leveraging skills in refactoring and unit testing, the work contributed to more stable CLI tooling and demonstrated a methodical approach to maintaining code quality and correctness.