added mailcow

config/services/mailcow.nix

@@ -0,0 +1,13 @@
+{ pkgs, ... }: {
+  networking.firewall.allowedTCPPorts = [ 25 110 143 465 587 993 995 4190 ];
+  environment.systemPackages = [ pkgs.docker-compose ];
+  virtualisation.docker = {
+    enable = true;
+    daemon.settings = {
+      ipv6 = true;
+      fixed-cidr-v6 = "fd00:dead:beef:c0::/80";
+      experimental = true;
+      ip6tables = true;
+    };
+  };
+}