diff --git a/modules/mailman.nix b/modules/mailman.nix
index 6f5bb2e..d7076b0 100644
--- a/modules/mailman.nix
+++ b/modules/mailman.nix
@@ -1,5 +1,9 @@
 { config, ... }:
 {
+  sops.secrets.mailman_ldap_search = {
+    key = "portunus_search";
+    owner = config.services.mailman.webUser;
+  };
   services.mailman = {
     enable = true;
     serve.enable = true;
@@ -7,5 +11,19 @@
     hyperkitty.enable = true;
     enablePostfix = true;
     siteOwner = "root@${config.fsr.domain}";
+    ldap = {
+      enable = true;
+      serverUri = "ldap://localhost";
+      bindDn = "uid=search, ou=users, dc=ifsr, dc=de";
+      bindPasswordFile = config.sops.secrets.mailman_ldap_search.path;
+      userSearch = {
+        ou = "ou=users, dc=ifsr, dc=de";
+        query = "(&(objectClass=posixAccount)(uid=%(user)s))";
+      };
+      groupSearch = {
+        ou = "ou=groups, dc=ifsr, dc=de";
+        query = "(objectClass=groupOfNames)";
+      };
+    };
   };
 }