@interop/data-integrity-proof

Data Integrity Proof library (@interop/data-integrity-proof)

DataIntegrity library for use with cryptosuites and jsonld-signatures.

This is a TypeScript, isomorphic (Node.js / browser / React Native) fork of @digitalbazaar/data-integrity. It is written in TypeScript and builds to ESM, swaps the base-encoding and SHA-256 implementations to per-environment variants (node:crypto, WebCrypto, and @noble/hashes for React Native), and uses the @interop/ forks of its dependencies.

Table of Contents

• Background
• Install
• Usage
• Contribute
• License

Background

For use with @interop/jsonld-signatures.

See also related specs:

• Verifiable Credential Data Integrity

Install

• Node.js 24+, browsers, and React Native are supported.

To install from NPM:

pnpm add @interop/data-integrity-proof

To install locally (for development):

git clone https://github.com/interop-alliance/data-integrity-proof.git
cd data-integrity-proof
pnpm install

Usage

The following code snippet provides a complete example of digitally signing a verifiable credential using this library:

import { Ed25519VerificationKey } from '@interop/ed25519-verification-key'
import { DataIntegrityProof } from '@interop/data-integrity-proof'
import { eddsaRdfc2022 } from '@interop/ed25519-signature'
import jsigs from '@interop/jsonld-signatures'
const {
  purposes: { AssertionProofPurpose }
} = jsigs

// create the unsigned credential
const unsignedCredential = {
  '@context': [
    'https://www.w3.org/2018/credentials/v1',
    {
      AlumniCredential: 'https://schema.org#AlumniCredential',
      alumniOf: 'https://schema.org#alumniOf'
    }
  ],
  id: 'http://example.edu/credentials/1872',
  type: ['VerifiableCredential', 'AlumniCredential'],
  issuer: 'https://example.edu/issuers/565049',
  issuanceDate: '2010-01-01T19:23:24Z',
  credentialSubject: {
    id: 'https://example.edu/students/alice',
    alumniOf: 'Example University'
  }
}

// create the keypair to use when signing
const controller = 'https://example.edu/issuers/565049'
const keyPair = await Ed25519VerificationKey.from({
  '@context': 'https://w3id.org/security/multikey/v1',
  type: 'Multikey',
  controller,
  id: controller + '#z6MkwXG2WjeQnNxSoynSGYU8V9j3QzP3JSqhdmkHc6SaVWoT',
  publicKeyMultibase: 'z6MkwXG2WjeQnNxSoynSGYU8V9j3QzP3JSqhdmkHc6SaVWoT',
  secretKeyMultibase:
    'zrv3rbPamVDGvrm7LkYPLWYJ35P9audujKKsWn3x29EUiGwwhdZQd' +
    '1iHhrsmZidtVALBQmhX3j9E5Fvx6Kr29DPt6LH'
})

// create suite
const suite = new DataIntegrityProof({
  signer: keyPair.signer(),
  cryptosuite: eddsaRdfc2022
})

// create signed credential (documentLoader must resolve the key's controller
// document and verification method; see test/node/documentLoader.ts)
const signedCredential = await jsigs.sign(unsignedCredential, {
  suite,
  purpose: new AssertionProofPurpose(),
  documentLoader
})

Note: To create or verify proofs using legacy draft data integrity suites, you must pass legacyContext: true when creating a DataIntegrityProof instance; this will cause the appropriate legacy data integrity context (https://w3id.org/security/data-integrity/v1) to be used.

Contribute

PRs accepted.

If editing the Readme, please conform to the standard-readme specification.

License

MIT License 2026 Interop Alliance.