diff --git a/hosts/hainich/services/mail.nix b/hosts/hainich/services/mail.nix
index 9e98c5b..944f339 100644
--- a/hosts/hainich/services/mail.nix
+++ b/hosts/hainich/services/mail.nix
@@ -11,7 +11,7 @@ in {
     mailDirectory = "/data/mail";
     enable = true;
     fqdn = "mail.hacc.space";
-    domains = [ "hacc.space" "hacc.earth" "4future.dev" "4futu.re" "infra4future.de" "discuss.infra4future.de" ];
+    domains = [ "hacc.space" "muc.hacc.space" "hacc.earth" "4future.dev" "4futu.re" "infra4future.de" "discuss.infra4future.de" ];
 
     loginAccounts = {
         "hexchen@hacc.space".hashedPassword = "$6$x9skYtRp4dgxC$1y8gPC2BuVqG3kJVSMGgzZv0Bg1T9qxcnBWLIDbANy1d//SQ23Y7s3IMYcEPd1/l/MYWD9Y/Qse6HbT5w5Xwq/";
@@ -97,6 +97,12 @@ in {
             "stuebinm@hacc.space"
             "lenny@hacc.space"
         ];
+
+        # -- c3 world operation centre --
+        "world@muc.hacc.space" = [
+            "hexchen@hacc.space"
+            "stuebinm@hacc.space"
+        ];
     };
 
     # Use Let's Encrypt certificates. Note that this needs to set up a stripped
@@ -132,6 +138,7 @@ in {
     haccvoc@infra4future.de voc@hacc.space
     contact@hacc.space info@hacc.space
     himmel@hacc.space admin@hacc.space
+    divoc-patches@muc.hacc.space world@muc.hacc.space
   '';
 
   systemd.services.alps = {