diff --git a/machines/pendulum/matrix.nix b/machines/pendulum/matrix.nix
index 7495d90..8882fa2 100644
--- a/machines/pendulum/matrix.nix
+++ b/machines/pendulum/matrix.nix
@@ -45,8 +45,8 @@
   systemd.services.synapse-db-cleanup = {
     serviceConfig = {
       Type = "oneshot";
-      User = "postgres";
-      Group = "postgres";
+      User = "matrix-synapse";
+      Group = "matrix-synapse";
     };
     path = with pkgs; [ matrix-synapse-tools.rust-synapse-compress-state ];
     script = ''