[dgb23]

I guess the important (and hard) part is to not make a categorical error and mix up design of high level functionality and UI with the plumbing underneath it.

The plumbing also needs iteration and prototyping, but sound, forward looking decisions at the right time pay dividends later on. That includes putting extra effort and thinking into data structures, error handling, logging, naming etc. rather earlier than later. All of that stuff makes iterating on the higher levels much easier very quickly.