System Extensions and DriverKit
System extensions on macOS Catalina allow software like network extensions and endpoint security solutions to extend the functionality of macOS without requiring kernel-level access. DriverKit provides a fully modernized replacement for IOKit to create device drivers. System extensions and drivers built with DriverKit run in user space, where they can’t compromise the security or stability of macOS. Once installed, an extension is available to all users on the system and can perform tasks previously reserved for kernel extensions.