diff --git a/meta/options.nix b/meta/options.nix
index 389fd61..98b2375 100644
--- a/meta/options.nix
+++ b/meta/options.nix
@@ -67,6 +67,39 @@ in
           Groups of the DGNum organization.
         '';
       };
+
+      external = mkOption {
+        type = attrsOf (listOf str);
+        description = ''
+          External services used by the DGNum organization.
+        '';
+      };
+
+      services = mkOption {
+        type = attrsOf (submodule {
+          options = {
+            admins = mkOption {
+              type = listOf str;
+              default = [ ];
+              description = ''
+                List of administrators of the service.
+              '';
+            };
+
+            adminGroups = mkOption {
+              type = listOf str;
+              default = [ ];
+              description = ''
+                List of administrator groups of the service.
+              '';
+            };
+          };
+        });
+        description = ''
+          Administrator access of the different DGNum services,
+          it is mainly indicative as most services cannot configure this statically.
+        '';
+      };
     };
 
     nodes = mkOption {
diff --git a/meta/organization.nix b/meta/organization.nix
index 00cc14c..7196988 100644
--- a/meta/organization.nix
+++ b/meta/organization.nix
@@ -48,4 +48,38 @@
     # members of this group are root on the fai infrastructure
     fai = [ "catvayor" ];
   };
+
+  external = {
+    dns = [
+      "thubrecht"
+      "raito"
+    ];
+
+    email = [ "raito" ];
+
+    irc = [ "raito" ];
+  };
+
+  services = {
+    # Démarches Normaliennes
+    ds-fr.admins = [
+      "thubrecht"
+      "jemagius"
+    ];
+
+    # Cloud DGNum
+    nextcloud.admins = [
+      "thubrecht"
+      "raito"
+    ];
+
+    # Netbox DGNum
+    netbox.adminGroups = [
+      "root"
+      "fai"
+    ];
+
+    # Videos DGNum
+    peertube.admins = [ "thubrecht" ];
+  };
 }