diff --git a/outputs.nix b/outputs.nix
index b26e229..41e50d6 100644
--- a/outputs.nix
+++ b/outputs.nix
@@ -60,7 +60,7 @@ self = {
       ( lib.filterAttrs (name: type:
         (
           (type == "regular" && lib.hasSuffix ".nix" name)
-          || (type == "directory" && builtins.pathExists "${./.}/hosts/${name}/default.nix")
+          || (type == "directory" && builtins.pathExists "${builtins.toString ./.}/hosts/${name}/default.nix")
         )
         && !lib.hasPrefix "." name
       ))