diff --git a/spec/library/default.nix b/spec/library/default.nix
index e69ec41d..c3b00584 100644
--- a/spec/library/default.nix
+++ b/spec/library/default.nix
@@ -32,5 +32,6 @@
   boot.kernelModules = [ "kvm-intel" ];
   boot.extraModulePackages = [ ];
   boot.kernelParams = [ "console=ttyS0,115200n8" ];
+  networking.firewall.allowedTCPPorts = [ 25565 ];
   environment.systemPackages = with pkgs; [ python3 ];
 }