Problem
Operational artifacts can lose provenance, sequence and execution context when copied, packaged or reviewed outside the originating runtime.
ENGINEERING CASE STUDY
Make released evidence independently inspectable.
The problem was not merely storing logs. The problem was preserving attributable state after evidence leaves the runtime that produced it.
Architecture
Blackbox separates receipt-chain semantics, deterministic hashing, detached signatures, durable append, declared release manifests and independent verification.
Observed proof
The current repository proof probe records 348 deterministic receipts; the referenced manifest records 85 Python files compiling and a five-test pytest pass.
Boundary
The canonical million-case contract remains a target gate. This engineering case does not represent an external customer deployment or legal-admissibility certification.