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.
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CuerdOS
CuerdOS is a Debian-based GNU/Linux distribution with focus on stability, efficiency and performance. It comes with a series of optimisations, such as performance and memory consumption improvements.