diff --git a/nixos/common.nix b/nixos/common.nix
index 7ecd3f06..48f32ed8 100644
--- a/nixos/common.nix
+++ b/nixos/common.nix
@@ -107,4 +107,7 @@ in {
   };
 
   system = { inherit stateVersion; };
+  system.activationScripts.diff = ''
+    ${pkgs.nvd}/bin/nvd --nix-bin-dir=${pkgs.nix}/bin diff /run/current-system "$systemConfig"
+  '';
 }
diff --git a/nixos/server-common.nix b/nixos/server-common.nix
index a5f4dca6..6a8149f2 100644
--- a/nixos/server-common.nix
+++ b/nixos/server-common.nix
@@ -12,4 +12,7 @@
     enableNsncd = true;
   };
   system.stateVersion = "22.11";
+  system.activationScripts.diff = ''
+    ${pkgs.nvd}/bin/nvd --nix-bin-dir=${pkgs.nix}/bin diff /run/current-system "$systemConfig"
+  '';
 }