I've been working on a prompt to application product[1] and one of the approaches we tried was test driven development. We would have the LLM write tests based on a detailed description of the application. Then give the LLM the tests and the requirements and ask it to write the application.

The thinking is we could run the tests to verify that the requirements are functional (assuming it wrote the tests correctly in the first place - in many cases it did, fyi).

The problem was that it was too fickle. Sometimes the failing tests caught application bugs. But too often the LLM just couldn't get the tests to pass even though sometimes the application was working fine.

It resulted in a terrible user experience (they only see latency of getting the application correctly written or a failure if it gives up).

That being said, I think a lot of the issues folks like us find with LLMs are because we haven't figured out how and what to ask.

Ultimately, we found an alternative approach which gets at least 95% of the application working 100% of the time. And this is actually a MUCH better user experience than waiting forever to sometimes just get "Sorry, we couldn't create your application.".

[1] https://withlattice.com