diff --git a/nixbld-etc-nixos/configuration.nix b/nixbld-etc-nixos/configuration.nix
index 5525f0d..3565771 100644
--- a/nixbld-etc-nixos/configuration.nix
+++ b/nixbld-etc-nixos/configuration.nix
@@ -1251,6 +1251,32 @@ in
       ExecStart = "${pkgs.bash}/bin/bash -c 'PATH=${pkgs.rt}/bin HOME=/tmp ${pkgs.fetchmail}/bin/fetchmail -f /etc/nixos/secret/rt_fetchmailrc'";
     };
   };
+  systemd.services.ssh-tunnel-intl = {
+      description = "SSH Tunnel to Intl";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "sockets.service" ];
+      serviceConfig = {
+        Restart = "on-failure";
+        User = "hydra-queue-runner"; # TODO needs new user both here and there
+        Group = "hydra";
+        ExecStart = "${pkgs.openssh}/bin/ssh -N -L 127.0.0.1:1587:5.78.86.156:1587 zolaupd@5.78.86.156";
+      };
+    };
+
+  environment.etc."postfix/sender_relay".text = ''
+      @m-labs-intl.com [localhost]:1587
+      @m-labs.hk :
+      @m-labs.ph :
+      @193thz.com :
+      @malloctech.fr :
+  '';
+  systemd.services.postfix-rebuild-sender-relay = {
+      description = "Postfix Rebuild Sender Dependent Relayhost Maps";
+      serviceConfig = {
+        ExecStart = "${pkgs.postfix}/sbin/postmap /etc/postfix/sender_relay";
+      };
+      wantedBy = [ "multi-user.target" ];
+  };
 
   mailserver = {
     enable = true;
@@ -1260,8 +1286,14 @@ in
     enablePop3 = true;
     enablePop3Ssl = true;
     certificateScheme = "acme-nginx";
-    policydSPFExtraConfig = "skip_addresses = 5.78.86.156,2a01:4ff:1f0:83de::1";
   } // (import /etc/nixos/secret/email_settings.nix);
+  services.postfix = {
+    config = {
+      sender_dependent_relayhost_maps = "hash:/etc/postfix/sender_relay";
+      postscreen_upstream_proxy_protocol = "haproxy";
+      postscreen_upstream_proxy_timeout = "5s";
+    };
+  };
   services.roundcube = {
     enable = true;
     hostName = "mail.m-labs.hk";