diff --git a/nixbld-etc-nixos/configuration.nix b/nixbld-etc-nixos/configuration.nix
index c6a87f7..ab33e33 100644
--- a/nixbld-etc-nixos/configuration.nix
+++ b/nixbld-etc-nixos/configuration.nix
@@ -1184,14 +1184,18 @@ in
         Restart = "on-failure";
         User = "hydra-queue-runner"; # TODO needs new user both here and there
         Group = "hydra";
-        ExecStart = "${pkgs.openssh}/bin/ssh -N -L 127.0.0.1:1587:5.78.86.156:1587 zolaupd@5.78.86.156";
+        ExecStart = "${pkgs.openssh}/bin/ssh -N -D 127.0.0.1:1587 zolaupd@5.78.86.156";
       };
     };
 
   environment.etc."postfix/sender_relay".text = ''
-      @m-labs-intl.com [localhost]:1587
+      m-labs-intl.com socks:
       * :
   '';
+  environment.etc."tsocks.conf".text = ''
+    server = 127.0.0.1
+    server_port = 1587
+  '';
   systemd.services.postfix-rebuild-sender-relay = {
       description = "Postfix Rebuild Sender Dependent Relayhost Maps";
       serviceConfig = {
@@ -1214,6 +1218,11 @@ in
       sender_dependent_relayhost_maps = "hash:/etc/postfix/sender_relay";
       postscreen_upstream_proxy_protocol = "haproxy";
       postscreen_upstream_proxy_timeout = "5s";
+      masterConfig.socks = {
+        type = "unix";
+        command = "pipe";
+        args = "flags=R user=nobody argv=${pkgs.tsocks}/bin/tsocks ${pkgs.postfix}/bin/sendmail -oi -f $sender $recipient";
+      };
     };
   };
   services.roundcube = {