Evidence Layer
Internal component of The VeilForensic proof of every AI decision.
The evidence layer of The Veil creates cryptographically signed, tamper-evident records of every AI decision. When regulators, auditors, or customers ask what your AI did and why — you have forensic proof, not logs.
The Provenance Gap
What auditors see today
- Application logs that can be altered after the fact
- No cryptographic integrity — anyone with DB access can edit
- Timestamps from your own servers, not independently verifiable
- No chain linking — records can be deleted without trace
What the evidence layer provides
- Ed25519-signed decision envelopes — tamper-evident by design
- SHA-256 hash chain — each record links to the previous one
- RFC 3161 timestamps from independent authorities
- Optional Sigstore Rekor publication — public, append-only proof
How It Works
Decision Event
Your ApplicationYour AI call — whether a direct API request, an agent workflow, or a custom pipeline — is routed through The Veil gateway. The gateway captures what was decided, inputs considered, model used, confidence score.
Cryptographic Signing
The Veil GatewayThe Veil gateway signs the record with Ed25519. Each record chains to the previous one via SHA-256 hash chain.
Independent Timestamp
External TSAAn RFC 3161 Timestamp Authority co-signs with a qualified timestamp. The record is now provably dated by a third party.
Transparency Log
Rekor (Public)Optionally published to Sigstore Rekor — a public, append-only transparency log. Anyone can verify the record existed at that time.
Automatically Engaged
No customer-installed package. The evidence layer is part of The Veil — every request that passes through the gateway is signed, chained, timestamped, and optionally published, without any code change on your side. When you adopt The Veil, you get evidence for free.
- No SDK to install, no imports to wire up
- Engaged by default on every gateway request
- Records are retrievable via The Veil control surface
- Export any decision as a signed PDF certificate
What You Get
Forensic Decision Records
Signed, chained, independently timestamped decision envelopes that hold up under regulatory scrutiny.
EU AI Act Article 14 Ready
Decision records map directly to Article 14 human oversight requirements. Enforcement begins August 2, 2026.
PDF Decision Certificates
Export any decision as a signed PDF certificate. Hand your auditor a document, not a database query.
Hash Chain Integrity
Every record links to the previous via SHA-256. Deleting or altering any record breaks the chain — tampering is immediately detectable.
Internal Component
The evidence layer is part of The Veil, not a separate product. It ships with every Veil engagement at no extra cost and under the same contract.
Compliance Mapping
| Regulation | Requirement | Evidence layer response |
|---|---|---|
| EU AI Act Art. 14 | Human oversight with sufficient records | Signed decision records with full input/output provenance |
| EU AI Act Art. 12 | Automatic logging of AI system operation | Cryptographic hash chain — append-only, tamper-evident |
| GDPR Art. 22 | Meaningful information about automated decisions | Decision records include model, inputs, confidence, reasoning |
| DORA Art. 11 | ICT incident logging and reporting | Independent TSA timestamps prove when decisions occurred |
Part of The Veil, not a separate product.
The evidence layer is the cryptographic provenance component of The Veil. It ships with every engagement and is scoped alongside the rest of the pipeline — it is not sold or purchased on its own, and there is no self-serve purchase path today.
Combined with the split-knowledge pipeline, you get identity-separated decision provenance — the AI that made the decision never knew who it was about, and you can prove it.
Talk to us about AI decision evidence