diff --git a/lib/build-clan/eval-docs.nix b/lib/build-clan/eval-docs.nix
index bac768666..5ac1aca7d 100644
--- a/lib/build-clan/eval-docs.nix
+++ b/lib/build-clan/eval-docs.nix
@@ -1,6 +1,7 @@
 { pkgs, lib }:
 let
   eval = lib.evalModules {
+    class = "nixos";
     modules = [
       ./interface.nix
     ];
diff --git a/lib/inventory/eval-clan-modules/default.nix b/lib/inventory/eval-clan-modules/default.nix
index 84b334635..6d147919c 100644
--- a/lib/inventory/eval-clan-modules/default.nix
+++ b/lib/inventory/eval-clan-modules/default.nix
@@ -28,6 +28,7 @@ let
     }:
     let
       evaled = lib.evalModules {
+        class = "nixos";
         modules = [
           (baseModule { inherit pkgs; })
           {
@@ -83,6 +84,7 @@ let
             name = role;
             value =
               (lib.evalModules {
+                class = "nixos";
                 modules = [
                   (baseModule { inherit pkgs; })
                   clan-core.nixosModules.clanCore