vc-sdk

Universal W3C VC Data Model v2.0 TypeScript SDK

@attestto/vc-sdk is a foundational SDK for issuing and verifying Verifiable Credentials with zero native dependencies. Implements the full W3C VC Data Model v2.0 specification. Designed to be extended by domain-specific credential packages via a pluggable schema system. For full documentation, see attestto.org/docs.

Architecture

graph LR
    A["vc-sdk<br/>(core API)"]
    B["cr-vc-sdk<br/>(CR types)"]
    C["cr-vc-schemas<br/>(JSON-LD contexts)"]
    D["attestto-app<br/>(citizen wallet)"]
    E["attestto-verify<br/>(verification UI)"]
    
    A --> B
    A --> E
    B --> C
    B --> D
    A --> D

Quick start

Prerequisites

• Node ≥ 18
• npm or yarn

Install

npm install @attestto/vc-sdk

Try it

import { VCIssuer, VCVerifier, generateKeyPair } from '@attestto/vc-sdk'

// Generate keys (Ed25519 or ES256)
const keys = generateKeyPair()

// Create an issuer
const issuer = new VCIssuer({
  did: 'did:web:my-org.attestto.id',
  privateKey: keys.privateKey,
})

// Issue any credential — no type constraints
const vc = await issuer.issue({
  type: 'UniversityDegree',
  context: 'https://schemas.example.org/education/v1',
  subjectDid: 'did:web:student.attestto.id',
  claims: {
    degree: {
      name: 'Computer Science',
      level: 'Bachelor',
      university: 'Universidad de Costa Rica',
    },
  },
})

// Verify
const verifier = new VCVerifier()
const result = await verifier.verifyWithKey(vc, keys.publicKey, 'Ed25519', {
  expectedType: 'UniversityDegree',
  expectedIssuer: 'did:web:my-org.attestto.id',
})
console.log(result.valid) // true

API

VCIssuer

const issuer = new VCIssuer(config: IssuerConfig)
issuer.use(plugin: SchemaPlugin)          // Register domain schemas
const vc = await issuer.issue(options)     // Issue a signed VC

Core responsibilities: sign VCs with Ed25519 or ES256, manage DID/keyId, auto-inject schema context and property mapping via plugins.

VCVerifier

const verifier = new VCVerifier(config?: VerifierConfig)
const result = await verifier.verify(vc, options?)
const result = await verifier.verifyWithKey(vc, publicKey, algorithm, options?)

Validates signatures, expiration, proof format, and custom constraints. Returns { valid, checks, errors, warnings }.

generateKeyPair

const keys = generateKeyPair('Ed25519' | 'ES256')
// keys.publicKey: Uint8Array
// keys.privateKey: Uint8Array
// keys.algorithm: string

Generate cryptographic key pairs for issuance and verification.

SchemaPlugin

interface SchemaPlugin {
  context: string                    // JSON-LD context URL
  types: string[]                    // Credential types this plugin handles
  propertyMap?: Record<string, string>  // Map type → credentialSubject property
}

Register domain-specific schemas to auto-inject context and wrap claims:

issuer.use({
  context: 'https://schemas.attestto.org/cr/driving/v1',
  types: ['DrivingLicense', 'TheoreticalTestResult'],
  propertyMap: {
    DrivingLicense: 'license',
    TheoreticalTestResult: 'theoreticalTest',
  },
})

// Now issue — context and property wrapping are automatic
const vc = await issuer.issue({
  type: 'DrivingLicense',
  subjectDid: 'did:web:maria.attestto.id',
  claims: { licenseNumber: 'CR-2026-045678', categories: ['B'] },
})

Ecosystem

Full index: Attestto-com/attestto-open

| Repo | What | |---|---| | vc-sdk | This — universal VC SDK | | cr-vc-sdk | CR-specific SDK (TypeScript, typed wrappers) | | cr-vc-sdk-dotnet | CR-specific SDK (.NET 8) | | cr-vc-schemas | CR driving schemas (11 types) | | did-sns-spec | did:sns DID method spec | | did-sns-resolver | Universal Resolver driver for did:sns | | id-wallet-adapter | Wallet discovery protocol |

License

Apache 2.0