diff --git a/packages/nixos/system.nix b/packages/nixos/system.nix
index 553accc304..ed36be1223 100644
--- a/packages/nixos/system.nix
+++ b/packages/nixos/system.nix
@@ -47,6 +47,7 @@
       "/" = {
         device = "/dev/mapper/root";
         fsType = "erofs";
+        options = [ "ro" ];
       };
     }
     # Create tmpfs on directories that need to be writable for activation.
@@ -72,10 +73,6 @@
         ]
     );
 
-  # We cant remount anything in the userspace, as we already
-  # have the rootfs mounted read-only from the initrd.
-  systemd.suppressedSystemUnits = [ "systemd-remount-fs.service" ];
-
   networking.firewall.enable = false;
 
   nixpkgs.hostPlatform.system = "x86_64-linux";