diff --git a/nixos/modules/services/web-apps/gerrit.nix b/nixos/modules/services/web-apps/gerrit.nix
index ad8cf63ac424..c1af294c7cd8 100644
--- a/nixos/modules/services/web-apps/gerrit.nix
+++ b/nixos/modules/services/web-apps/gerrit.nix
@@ -234,6 +234,7 @@ in
         LockPersonality = true;
         NoNewPrivileges = true;
         PrivateDevices = true;
+        PrivateMounts = true;
         PrivateTmp = true;
         ProtectClock = true;
         ProtectControlGroups = "strict";