Worked on enhancing SELinux testing support in the yuwata/systemd repository by integrating policy packages into the openSUSE mkosi configuration, enabling automated end-to-end SELinux policy testing within continuous integration workflows. This involved system administration, build systems, and testing skills to ensure robust policy integration and improved test coverage. Additionally, addressed a critical bug in the 89luca89/distrobox repository by fixing newline handling when appending user data to /etc/passwd and /etc/group, which improved the reliability of user creation during container initialization. Demonstrated proficiency in Linux environments and shell scripting, with careful attention to configuration management and system-level reliability.