I’ve been wondering about something similar - a system that enforces (or does the heavy lifting) of dividing a large task into smaller sub-tasks so that it’s easy to run/check/test each one independently - even on a fresh model instance if needed.
This is based on the observation that the medium-sized open weight models (~20-35b) are very able to one-shot smaller discrete tasks but seem to lose their way project managing themselves through larger tasks that have multiple steps.