{ lib, ... }: 
let
  impermanence =  builtins.fetchTarball "https://github.com/nix-community/impermanence/archive/master.tar.gz";
in
{
  boot.initrd.postResumeCommands = lib.mkAfter ''
    mkdir /btrfs_tmp
    mount /dev/mapper/crypted /btrfs_tmp
    if [[ -e /btrfs_tmp/@root ]]; then
        mkdir -p /btrfs_tmp/@old_roots
        timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/root)" "+%Y-%m-%-d_%H:%M:%S")
        mv /btrfs_tmp/@root "/btrfs_tmp/@old_roots/$timestamp"
    fi
  
    delete_subvolume_recursively() {
        IFS=$'\n'
        for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
            delete_subvolume_recursively "/btrfs_tmp/$i"
        done
        btrfs subvolume delete "$1"
    }
  
    for i in $(find /btrfs_tmp/@old_roots/ -maxdepth 1 -mtime +10); do
        delete_subvolume_recursively "$i"
    done
  
    btrfs subvolume create /btrfs_tmp/@root
    umount /btrfs_tmp
  '';

  imports = [ "${impermanence}/nixos.nix" ];

  environment.persistence."/persist" = {
    enable = true;
    hideMounts = true;
    directories = [
      "/var/log"
      "/var/lib/bluetooth"
      "/var/lib/nixox"
      "/var/lib/systemd/coredump"
      "/etc/NetworkManager/system-connections"
    ];
    files = [
      "/etc/machine-id"
    ];
    users.louis = {
      directories = [
        "Documents"
	"Downloads"
      ];
    };
  };

  fileSystems."/persist".neededForBoot = true;

}