Verifiable Credential

A Verifiable Credential, usually shortened to VC, is a digitally signed statement one party makes about another, built so that anyone can check it's genuine without calling the party who made it.

Think of a passport. A government (the issuer) states that a person (the subject, usually also the holder) is a citizen of a country. A border officer (the verifier) doesn't call the passport office every time it's shown, the document itself carries enough proof (the photo, the watermark, the chip) to check on the spot. A Verifiable Credential does the same job in software: a cryptographic signature stands in for the watermark, and any verifier can check that signature against the issuer's public key with no phone call to the issuer required.

A Solidus KYC credential has this shape (the identifiers below are illustrative):

{
  "@context": [
    "https://www.w3.org/2018/credentials/v1",
    "https://solidus.network/credentials/v1"
  ],
  "type": ["VerifiableCredential", "KycLevel1Credential"],
  "issuer": "did:solidus:4Wp9xKjRvNmQ3eYhT8bC2aFs7gDzLpUk",
  "credentialSubject": {
    "id": "did:solidus:7Hk3mRtQZvNxP2bK9wYfJ4eD6cA5sLgR",
    "kycLevel": 1,
    "country": "DE"
  },
  "proof": {
    "type": "Ed25519Signature2020",
    "verificationMethod": "did:solidus:4Wp9xKjRvNmQ3eYhT8bC2aFs7gDzLpUk#key-1",
    "proofPurpose": "assertionMethod"
  }
}

The design point that matters commercially: a Verifiable Credential is issued once, then held by its subject, not re-verified from scratch by every party who later needs to check it. That reuse is the entire bet behind Solidus Verify (see Issuer-Holder-Verifier triangle).

Where it comes from

The data model, the terminology (issuer / holder / subject / verifier), and the JSON-LD @context mechanism all come from the W3C Verifiable Credentials Working Group. Manu Sporny and Dave Longley of Digital Bazaar have been long-standing editors on the spec, alongside many other contributors across the working group's history. Solidus designed none of this, we implement it and sign real credentials against it in production.

Solidus status

Shipped. verify.solidus.network issues real credentials today. Two signature types exist: Ed25519 (the default, no special caveat) and BBS+ (enables selective disclosure, live on testnet, but unaudited; external audit targeted H2 2026 via NLnet NGI Zero).

Proof you can run yourself: npm i @solidus-network/sdk and read the issued credential object directly: its shape is exactly the JSON above.