diff --git a/nixos/modules/mailman.nix b/nixos/modules/mailman.nix
index 597a2f1..71403e6 100644
--- a/nixos/modules/mailman.nix
+++ b/nixos/modules/mailman.nix
@@ -11,16 +11,16 @@
     mkEnableOption
     mkOption
     ;
-  inherit (lib.types) nonEmptyStr;
+  inherit (lib.types) str;
   cfg = config.services.mathebau-mailman;
 in {
   options.services.mathebau-mailman = {
     enable = mkEnableOption "mathebau mailman service";
     hostName = mkOption {
-      type = nonEmptyStr;
+      type = str;
     };
     siteOwner = mkOption {
-      type = nonEmptyStr;
+      type = str;
     };
   };