Steel Threads are a powerful but obscure software design approach
This reminds me of something John Carmack tweeted once (can't find the tweet).In the tweet, he said that when coding, he'd start by the smallest possible PoC, and code it entirely front to back. That'd give the general structure, and then he'd build upon that. (this is what I remember of it fwiw).I do this all the time too, which I think is a vastly superior approach to TDD, which assumes how an API is going to be used, without actually writing the actual thing that's going to use it.