modules/nixos: add upgrade-diff script

2 files changed, 13 insertions, 0 deletions

diff --git a/modules/nixos/base/default.nix b/modules/nixos/base/default.nix
index 63700e1..e788ded 100644
--- a/modules/nixos/base/default.nix
+++ b/modules/nixos/base/default.nix
@@ -17,6 +17,7 @@ in {
     ./root.nix
     ./security.nix
     ./systemd.nix
+    ./upgrade-diff.nix
     ./virtualisation.nix
   ];
 
diff --git a/modules/nixos/base/upgrade-diff.nix b/modules/nixos/base/upgrade-diff.nix
new file mode 100644
index 0000000..68be9af
--- /dev/null
+++ b/modules/nixos/base/upgrade-diff.nix
@@ -0,0 +1,12 @@
+{
+  config,
+  pkgs,
+  ...
+}: {
+  system.activationScripts."upgrade-diff" = {
+    supportsDryActivation = true;
+    text = ''
+      ${pkgs.nvd}/bin/nvd --nix-bin-dir=${config.nix.package}/bin diff /run/current-system "$systemConfig"
+    '';
+  };
+}