diff --git a/hosts/public-access-proxy/proxy.nix b/hosts/public-access-proxy/proxy.nix
index 7593c54d..c045365e 100644
--- a/hosts/public-access-proxy/proxy.nix
+++ b/hosts/public-access-proxy/proxy.nix
@@ -28,7 +28,7 @@ in
             type = lib.types.submodule {
               options = {
                 host = lib.mkOption {
-                  type = with lib.types; nullOr string;
+                  type = with lib.types; nullOr str;
                   default = null;
                   description = ''
                     Host to forward traffic to.