REF-074: Signing Is Not Enough

REF-074: Signing Is Not Enough

Citation

Ercan, G. (2026, April 16). Signing Is Not Enough: Why AI Artifact Provenance Needs to Be a Graph. Jozu Blog. https://jozu.com/blog/signing-is-not-enough-why-ai-artifact-provenance-needs-to-be-a-graph/

Local source corpus: `/home/roctinam/dev/research/research-papers` REF-742.

Document Profile

AttributeValue
Year2026
TypeEngineering blog / vendor position piece
Source statusWeb snapshot archived in local research corpus
GRADE / QualityB - practical standards-grounded article; vendor source and not empirical
AIWG RelevanceMedium - Clear lineage model for signed artifacts with multiple inputs

Executive Summary

Ercan argues that artifact signatures prove identity and integrity for one object but do not explain what produced it. For AI/ML artifacts, the useful provenance shape is a graph: a model output can depend on a base model, data, scanner results, build pipeline, and other artifacts, each with its own attestation chain.

AIWG web-resource releases are simpler than model builds, but the warning still applies. A signed release manifest is necessary, while the broader release story should also connect source commits, generated prebuilt indices, release host publication, lockfile state, and test evidence.

AIWG Implementation Mapping

Provenance-Graph ConceptAIWG Resource Implication
Multiple input artifactsBundle source, generated Fortemi export, raw resources, trust root
Digest-pinned dependenciesManifest and lockfile digests for every consumed resource
Recursive verificationFuture release evidence can trace source commit to published bundle
Attestation typesBuild, test, signing, and publication evidence should be distinct

Design Implications

  • Do not describe release signing as complete supply-chain assurance.
  • Preserve enough manifest and lockfile metadata to connect resource bytes back

to generation evidence.

  • Keep docs clear that provenance is layered: signatures, descriptors, lockfile,

CI evidence, and publication records each answer different questions.

Cross-References

  • REF-062: W3C PROV gives the general entity/activity/agent vocabulary.
  • REF-069: OCI registries are a common substrate for artifact and attestation

graphs.

  • REF-073: Registry provenance adds distribution authority to graph evidence.