diff --git a/services/mailserver.nix b/services/mailserver.nix
index 73848ad..1dad890 100644
--- a/services/mailserver.nix
+++ b/services/mailserver.nix
@@ -35,6 +35,7 @@ with lib;
   {
     mailserver = {
       enable = true;
+      stateVersion = 3;
       fqdn = fdomain;
       domains = [
         fdomain