diff --git a/nixbld-etc-nixos/hydra-binary-cache-store.patch b/nixbld-etc-nixos/hydra-binary-cache-store.patch
index 05217f3..1570e5b 100644
--- a/nixbld-etc-nixos/hydra-binary-cache-store.patch
+++ b/nixbld-etc-nixos/hydra-binary-cache-store.patch
@@ -44,7 +44,7 @@ index 71869ba0..4276f95a 100644
 +
 +        $path = "/" . $1 . "/nar/$path";
 +        my $fh = new IO::Handle;
-+        open $fh, "<", $path;
++        open $fh, "<:raw", $path;
 +        $c->response->body($fh);
 +    }
 +