diff --git a/mail-server.nix b/mail-server.nix
index b3c47ae..fb06c06 100644
--- a/mail-server.nix
+++ b/mail-server.nix
@@ -63,7 +63,7 @@ in {
     };
   };
 
-  config = mkif cfg.enable {
+  config = mkIf cfg.enable {
     services.nginx = {
       virtualHosts = {
         "${cfg.smtp.hostname}".locations."/metrics" = {