system-files
There are 4 repositories under system-files topic.
extratone/iOSSystemSounds
Sounds found in and extracted from System/Library/Audio/UISounds in multiple formats.
systemmgr/postfix
Postfix config files
SwetabhOfficial/Check-Hidden-files-System-Files-in-Windows-using-HTML
You can See/Play/Download/Run everything in your Windows E.g. Hidden files, Windows.exe files, every tools of windows etc.
systemmgr/cron
cron files