I don't think separate tool is a good idea for this.. that's what assertions in your main/config file are for. All you need is just 1 line: assert os.geten

I don't think separate tool is a good idea for this.. that's what assertions in your main/config file are for. All you need is just 1 line: assert os.getenv('DATABASE_URL'), "You forgot to set DATABASE_URL" and as a bonus other developers get this check too, even if they have no idea about this tool.