Alex Xu focused on improving build reliability for the systemd/systemd repository by addressing a bug related to header file inconsistencies. He modified the keyboard-keys-list generation script to reference the local input.h file rather than relying on the system version, which often differed and caused build failures. This change reduced the risk of header drift and improved build determinism across various environments, supporting more stable CI/CD processes. Alex applied his expertise in Meson build systems and shell scripting to manage header dependencies and coordinate changes across repositories. The work demonstrated careful attention to cross-environment stability and robust build system practices.