diff --git a/microvms/vaultwarden/configuration.nix b/microvms/vaultwarden/configuration.nix
index fb203ee..801afce 100644
--- a/microvms/vaultwarden/configuration.nix
+++ b/microvms/vaultwarden/configuration.nix
@@ -7,6 +7,7 @@
       source = "/nix/store";
       mountPoint = "/nix/.ro-store";
       tag = "ro-store";
+      proto = "virtiofs";
     }
   ];
   system.stateVersion = config.system.nixos.version;