Vanilla OS
Vanilla OS, a fixed-release distribution based on Debian (formerly Ubuntu, prior to version 2) with the GNOME desktop, is an immutable operating system. The core parts of the system are locked down to prevent unwanted changes and corruption from third-party applications or a faulty update.
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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.