evidenced software spec-driven 5 of 6 answers assumed · last checked 2026-10-11

Evidence: from 1 private assignment

Unfit when: Exploratory or UI-heavy work where behaviour is discovered by building, Repository-scale systems specified in prose, No automated check stands between regeneration and merge

Spec-as-source

The spec is the only thing people edit; code is derived from it. The third and strictest level in Böckeler’s spec-first / spec-anchored / spec-as-source framing.

Evidence so far (specs-as-source-survey-2026-10-10): feasible in narrow formal domains (Scania spec2code); regeneration from prose is non-deterministic (Böckeler on Tessl). The strongest empirical result found (Tufano et al.) supports specs as a reasoning step, not as the source. It also applies in a narrow sense wherever rules can be stored as data that a generic engine interprets: the records are the spec.