Qubes OS
Qubes OS is a free and open-source, security-oriented operating system for single-user desktop computing. Qubes OS leverages Xen-based virtualization to allow for the creation and management of isolated compartments called qubes.
VS
Void
Void is an independently-developed, general-purpose operating system based on the monolithic Linux kernel. It features a hybrid binary/source package management system which allows users to quickly install, update and remove software, or to build software directly from sources with the help of the XBPS source packages collection.