diff --git a/packages/build-support/hydrate-asset-directory/default.nix b/packages/build-support/hydrate-asset-directory/default.nix
index 64b7926..08fbea6 100644
--- a/packages/build-support/hydrate-asset-directory/default.nix
+++ b/packages/build-support/hydrate-asset-directory/default.nix
@@ -8,7 +8,7 @@ rootDir: let
 
   hydrate = index: fetchAsset { inherit index; };
 
-  isDvc = lib.strings.hasSuffix ".dvc";
+  isDvc = file: lib.strings.hasSuffix ".dvc" (toString file);
 
   relative = file: lib.strings.removePrefix prefix (toString file);