If you used an `IFilePath` provider as I suggested in the comment above, and not a string directory name, you would do `json_path = json_files_dir.child("user_admin_role.json")` which is more correct on non-UNIX-y platforms (while running Mimic on Windows is not a priority, it would be nice if it just worked there in case anyone has a Windows dev setup; no need to spin up a VM just to get your path separators right).