Worked on the pypa/pip repository to improve reliability of configuration path discovery for macOS users running Homebrew. Addressed an issue where multiple global configuration directories were not properly handled by normalizing and splitting directory values returned from appdirs.site_config_dirs. This solution enhanced cross-platform consistency and reduced misconfiguration reports by ensuring robust detection of configuration files across different Homebrew installations. Added targeted unit tests to validate the new logic, focusing on scenarios involving Homebrew system prefixes. Utilized Python for development and testing, demonstrating skills in system configuration, path handling, and maintainable code practices to support platform parity goals within the project.