Enable proper nix-index shell integration
diff --git a/modules/nix-index.nix b/modules/nix-index.nix
index 36d1977..26b07e8 100644
--- a/modules/nix-index.nix
+++ b/modules/nix-index.nix
@@ -3,7 +3,10 @@
   username,
   ...
 }: {
-  home.home.packages = [pkgs.nix-index];
+  home.programs.nix-index = {
+    enable = true;
+    enableZshIntegration = true;
+  };
 
   config.environment.persistence."/nix/persist".users.${username}.directories = [".cache/nix-index"];
 }