{ inputs, ... }: { flake.modules.nixos.boot = { config, lib, ... }: let cfg = config.tnix.boot; in { imports = [ inputs.impermanence.nixosModules.impermanence ]; options.tnix.boot.impermanence = { enable = lib.mkEnableOption "Enable impermanence"; }; config = lib.mkIf cfg.impermanence.enable { programs.fuse.userAllowOther = true; fileSystems."/persist".neededForBoot = true; environment.persistence."/persist" = { hideMounts = true; directories = [ "/var/log" "/var/lib" "/etc/NetworkManager/system-connections" ]; files = [ "/etc/ssh/ssh_host_ed25519_key" "/etc/ssh/ssh_host_ed25519_key.pub" "/etc/ssh/ssh_host_rsa_key" "/etc/ssh/ssh_host_rsa_key.pub" ]; }; boot.initrd.systemd = { enable = true; services.wipe-my-fs = { wantedBy = [ "initrd.target" ]; after = [ "initrd-root-device.target" ]; before = [ "sysroot.mount" ]; unitConfig.DefaultDependencies = "no"; serviceConfig.Type = "oneshot"; script = '' mkdir /btrfs_tmp mount /dev/disk/by-partlabel/disk-primary-root /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 $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do delete_subvolume_recursively "$i" done btrfs subvolume create /btrfs_tmp/root umount /btrfs_tmp ''; }; }; }; }; }