> seeing feedback on your design in minutes rather than weeks or even months.

Weeks and month for to wait for a feedback in developing software? Are you the sloth in zootopia?

The longest cycle for feedback for me has only been hours. And that was about redesigning the core architecture of an app. Otherwise, it’s like 10 minutes cycle if it’s edit-compile-run, 5 minutes if it’s REPL (lisp, bash, python,…).