Read this first
A crypto-agility.json manifest is a claim. Its `attestation.url` points at a QuantaKrypto attestation, which is that claim made checkable: a small JSON document, signed with a post-quantum signature (ML-DSA, FIPS 204) inside a FIPS 140-3 hardware security module, that binds a reviewed posture to a deterministic evidence report. You verify it with public files and no cooperation from us: check the signature against our published key, confirm that key is certified by our offline root, and re-run the scan to reproduce the evidence hash. If all three hold, the posture is what it says it is.
The crypto-agility manifest a project publishes at `/.well-known/crypto-agility.json` is, by design, a self-report. Our own IETF draft says so plainly: publishing a file does not prove the statements in it. The `attestation.url` field is where proof lives. When QuantaKrypto certifies a project, it issues an attestation: an independent, signed, logged record that a reader can verify without taking anyone's word for it.
What an attestation contains
An attestation is a compact JSON object. The load-bearing fields:
- subject — the domain, repository, and commit the attestation is about.
- posture — a readiness score, a conformance status (conformant, conditional, or nonconformant), a link to the full evidence report, and that report's `contentHash`.
- keyId — which online signing key produced the signature.
- ledgerIndex — the position of this attestation in the public transparency ledger.
- signature — a post-quantum ML-DSA signature over the canonical bytes of everything above.
The `contentHash` is the anchor to reality. It is a deterministic hash of the qScan evidence report, so an attestation cannot claim a posture the evidence does not support: re-run the scan and the hash either matches or it does not.
How it is signed
Signatures are produced with ML-DSA (FIPS 204) in AWS KMS, so the private key never leaves a FIPS 140-3 hardware security module. There are two keys, in the standard root-and-online split used by certificate authorities:
- an online key (ML-DSA-65) that signs attestations day to day, and
- an offline root key (ML-DSA-87) whose only job is to certify the online key and revoke it if needed.
One online key signs every attestation, ours and every certified project's, so a single published key set verifies all of them. Because it is post-quantum, the attestation stays verifiable even against an adversary with a quantum computer, which is the whole point of the posture it attests to.
Verify one yourself
Verification needs only public files. Given an attestation and the published key set (`https://quantakrypto.com/.well-known/attestation-keys.json`):
- Check the signature against the online public key named by `keyId`.
- Check the chain: confirm that online key is itself signed by the root key, and is within its validity window.
- Check revocation: confirm the key and the attestation are not in the published revocation list.
- Reproduce the evidence: re-run `qscan <subject> --format evidence` at the attested commit and confirm its `contentHash` equals the one in the attestation.
- Check the ledger: confirm the attestation is present in the append-only, timestamp-anchored transparency log.
The first three and the last are pure signature and JSON checks; a reference `verify-attestation.sh` performs them offline. The evidence step is what makes the score honest rather than asserted. If every check passes, you have an independently verified posture, not a claim you had to trust.
A signature is not an endorsement of the score
An attestation proves that QuantaKrypto reviewed a posture and that the evidence is genuine and unaltered. It does not mean the subject is risk-free, and a low score can still be attested: a conformant posture and a conditional one are both valid, signed statements. Read the status and the evidence, not just the badge. The signature guarantees the record is real, not that the cryptography underneath is perfect.
Where you will see it
In the crypto-agility adoption registry, a listing whose manifest links a QuantaKrypto attestation carries an "Attested by QuantaKrypto" badge. quantakrypto.com attests its own posture the same way, on every deploy, so the tooling is dogfooded rather than exempt. To have your own project attested, see certification.