IMO this is what makes rust excellent for LLM coding. Sure other languages support this type of design by interface, but I feel like Rust's compiler forces the LLM to conform to existing interfaces.

Another pattern related that I've found useful with multi-threaded programming is to hand code threading and signal interactions. Up to this point, I've only had at best over complexity and at worst complete failure wrt multi-threaded logic.

SoI make sure the core multi-threaded logic is sound. Then the LLM can do a resonable job once the "scaffolding" is in place.