diff --git a/mastus/configuration.nix b/mastus/configuration.nix
index cc7f1a0..01334ce 100644
--- a/mastus/configuration.nix
+++ b/mastus/configuration.nix
@@ -15,6 +15,7 @@
   boot.loader.grub.device = "/dev/vda";
 
   networking.hostName = "mastus"; # Define your hostname.
+  networking.domain = "gebner.org";
   networking.enableIPv6 = true;
 
   # Select internationalisation properties.