diff --git a/hosts/vulcan/default.nix b/hosts/vulcan/default.nix
index f58931e..27a65c4 100644
--- a/hosts/vulcan/default.nix
+++ b/hosts/vulcan/default.nix
@@ -19,6 +19,7 @@
 
       sessionVariables = {
         UNIVERSE_FLAKE_ROOT = "${config.home.homeDirectory}/universe";
+        UNIVERSE_MODE = "home-manager";
       };
     };
     nix.settings.use-xdg-base-directories = true;