You need to lock the specs and implementation plan and verify the implementation about the previous phase docs.

https://github.com/doubleuuser/rlm-workflow

> specs often drift from the implementation > Maybe that's exactly the goal that "codespeak" is trying to solve

Yes and yes. I think it's an important direction in software engineering. It's something that people were trying to do a couple decades ago but agentic implementation of the spec makes it much more practical.