IMO you may be biting off on the hype comments and descriptions, and assuming too much of the LLM. (Easy to do if reading HN or internet articles)

Approach the prompts concretely. You want it to work on x struct and y function in z module. You want it to follow the structure you already started working on. You want it to work like existing software Y, here's a link to its docs page on the topic. The result of computation A should be B, but it's currently showing as C.

Then it will work great and save you time for many classes of problems.