add impermenence to cloudnix

hosts/cloudnix/default.nix

@@ -1,10 +1,13 @@
 {
   configVars,
   outputs,
+  lib,
+
   ...
 }: let
   user = "admin";
   merlinIp = configVars.networking.addresses.merlin.ip;
+  btrfsMountDevice = "/dev/sda2";
 in {
   imports = [
     # Create users for this host
@@ -14,6 +17,13 @@ in {
     ./hardware-configuration.nix
     ../common/core
 
+    # Impermanence
+    ../common/optional/persistence.nix
+    (import ../common/disks/btrfs/impermanence.nix {
+      btrfsMountDevice = btrfsMountDevice;
+      lib = lib;
+    })
+
     # Import optional options
     ../common/optional/persistence.nix
     ../common/optional/openssh.nix