https://github.com/nix-community/impermanence
    Modules to help you handle persistent state on systems with ephemeral root storage 

2024
Vimjoyer - Perfect NixOS | Impermanence Setup 0:00 of 8:51
    https://www.youtube.com/watch?v=YPKwkWtK7l0
WillBush - Impermanent NixOS: on a VM + tmpfs root + flakes + LUKS 0:00 of 19:48
    https://www.youtube.com/watch?v=Nts-z1oqo6M
2023
Zaney - I Have Fallen In 💕 Love With ❄️ NixOS | A Basic Introduction To NixOS 0:00 of 18:44
    https://www.youtube.com/watch?v=uS8Bx8nQots
2020
https://elis.nu/blog/2020/05/nixos-tmpfs-as-root/
https://grahamc.com/blog/erase-your-darlings/