The blog post is talking about bringing this TDD the test driven development mindset to prompt engineering. There are some things that are fundamentally different between testing a prompt or working with AI and working with just a bit more deterministic code testing type framework. Right. And there's so many things moving right. You're like oh well chat GPT five or GPT five is out or GPT four turbos have the price and then just came out. They're like wait is that performing better or what are the trade off? That's a big difference. Yeah.