diff --git a/hosts/pioneer-momo-koeln/configuration.nix b/hosts/pioneer-momo-koeln/configuration.nix
index b52f7b44..49bb148e 100644
--- a/hosts/pioneer-momo-koeln/configuration.nix
+++ b/hosts/pioneer-momo-koeln/configuration.nix
@@ -28,7 +28,10 @@
   };
 
   # Enable the OpenSSH daemon.
-  services.openssh.enable = true;
+  services.openssh = {
+    enable = true;
+    openFirewall = true;
+  };
 
   system.stateVersion = "22.05";
 }