SDD and the Missing Half — knowledge evaporation in agentic development

SDD and the Missing Half of the Answer

Adam Tornhill published a piece today that I found myself nodding along to almost paragraph by paragraph. His argument: Spec-Driven Development, in its strong form, is a replay of the Model-Driven Architecture dream from the 1990s — and it will fail for the same reasons. Implementation is not the execution of a known scope. It is the discovery of scope that wasn’t known yet. He’s right. And I want to pick up where he stops. ...

May 28, 2026 · 4 min · Karl-Heinz Reichel