1 files changed, 53 insertions, 0 deletions
diff --git a/sys/boot/impermanence.nix b/sys/boot/impermanence.nix
new file mode 100644
index 0000000..4902239
--- /dev/null
+++ b/sys/boot/impermanence.nix
@@ -0,0 +1,53 @@
+{ config, lib, ... }:
+with lib; let
+  cfg = config.local.boot.impermanence;
+in
+{
+  options.local.boot.impermanence = {
+    enable = mkEnableOption "root fs impermanence";
+
+    #TODO: type correcto de files, directories?
+
+    directories = mkOption {
+      type = with lib.types; listOf (either str attrs);
+      default = [ ];
+    };
+
+    files = mkOption {
+      type = with lib.types; listOf (either str attrs);
+      default = [ ];
+    };
+  };
+
+  config = mkMerge [
+    {
+      local.boot.impermanence = {
+        directories = [
+          "/etc/lvm"
+          "/var/lib/nixos"
+          "/var/log"
+        ];
+
+        files = [
+          "/etc/machine-id"
+          "/var/lib/logrotate.status"
+        ];
+      };
+    }
+    (mkIf cfg.enable {
+      assertions = [
+        {
+          assertion = (config.fileSystems ? "/persist") && config.fileSystems."/persist".neededForBoot;
+          message = "Impermanence requires /persist to be a neededForBoot mountpoint";
+        }
+      ];
+
+      environment.persistence."/persist" = {
+        hideMounts = true;
+
+        files = cfg.files;
+        directories = cfg.directories;
+      };
+    })
+  ];
+}