diff --git a/modules/services/matrix/default.nix b/modules/services/matrix/default.nix
index 3849eaa4..05812bca 100644
--- a/modules/services/matrix/default.nix
+++ b/modules/services/matrix/default.nix
@@ -122,17 +122,23 @@
     users = {
       users = {
         matrix_appservice_slack = {
+          uid = 998;
           group = "matrix_appservice_slack";
           isSystemUser = true;
         };
         mautrix_whatsapp = {
+          uid = 997;
           group = "mautrix_whatsapp";
           isSystemUser = true;
         };
       };
       groups = {
-        matrix_appservice_slack = { };
-        mautrix_whatsapp = { };
+        matrix_appservice_slack = {
+          gid = 998;
+        };
+        mautrix_whatsapp = {
+          gid = 997;
+        };
       };
     };
 
diff --git a/modules/services/nextcloud/default.nix b/modules/services/nextcloud/default.nix
index eaa64074..a566cc41 100644
--- a/modules/services/nextcloud/default.nix
+++ b/modules/services/nextcloud/default.nix
@@ -45,5 +45,7 @@
       requires = [ "postgresql.service" ];
       after = [ "postgresql.service" ];
     };
+    users.users.nextcloud.uid = 996;
+    users.groups.nextcloud.gid = 996;
   };
 }
diff --git a/modules/services/nginx/default.nix b/modules/services/nginx/default.nix
index 319eb7aa..6041955a 100644
--- a/modules/services/nginx/default.nix
+++ b/modules/services/nginx/default.nix
@@ -90,6 +90,10 @@
           })
           config.chvp.services.nginx.hosts);
     };
-    users.users.nginx.extraGroups = [ "acme" ];
+    users.users = {
+      nginx.extraGroups = [ "acme" ];
+      acme.uid = 999;
+    };
+    users.groups.acme.gid = 999;
   };
 }