Developer Documentation
Welcome to the Hyperledger Identus developer documentation. This comprehensive guide provides everything you need to build decentralized identity applications using the Identus platform.
Getting Started
New to Identus? Start here to understand the fundamentals and get your development environment up and running.
🚀 Quick Start Guide
Follow our comprehensive quick start guide to:
- Deploy Issuer and Verifier Cloud Agents
- Set up Wallet SDKs (TypeScript, Swift, or Kotlin)
- Deploy and connect to a Mediator
- Create DIDs and credential schemas
- Issue your first verifiable credential
- Perform credential verification
Perfect for: Developers new to Identus or SSI who want to see the full flow in action.
Developer Resources
📱 SDKs
Build wallet applications for web and mobile platforms using our comprehensive SDKs:
TypeScript SDK
Build browser and Node.js applications with full support for:
- DIDComm messaging
- Credential issuance and presentation
- AnonCreds, SD-JWT, and JWT credentials
- OpenID for Verifiable Credentials
- Backup and recovery
Tutorials available:
- Storage with Pluto
- PRISM DID Management
- Connectionless & Out-of-Band
- SDK Verification
- Migration Guides
Swift SDK
Native iOS SDK for building wallet applications with Swift. Includes sample applications and complete API reference.
Kotlin Multiplatform SDK
Cross-platform SDK for Android, iOS, and JVM applications. Share code across platforms while maintaining native performance.
☁️ Cloud Agent
The Cloud Agent provides REST API endpoints for enterprise SSI operations. It can act as an Issuer, Holder, or Verifier.
Tutorials
Step-by-step guides covering:
- Connections - Establish DIDComm connections between agents
- DIDs - Create, publish, update, and deactivate DIDs
- Schemas - Define and manage credential schemas
- Credential Definitions - Set up AnonCreds credential definitions
- Credential Issuance - Issue credentials via DIDComm and OID4VCI
- Credential Verification - Request and verify presentations
- Multi-tenancy - Manage multiple tenants and access control
- Webhooks - Subscribe to agent events
- Secrets Management - Secure key and secret storage
Cloud Agent Configuration
Essential guides for deploying and configuring the Cloud Agent:
- Building Blocks - Understanding Apollo, Castor, Pollux, and Mercury modules
- Authentication - API key and JWT authentication setup
- DID Management - Managing DIDs in the Cloud Agent
- Environment Variables - Complete configuration reference
- Secrets Storage - Vault and database secret management
- VDR Configuration - Verifiable Data Registry setup
- Troubleshooting - Common issues and considerations
Core Concepts
Before diving deep, familiarize yourself with these essential concepts:
- Self-Sovereign Identity (SSI) - User-controlled digital identity
- Decentralized Identifiers (DIDs) - Globally unique identifiers you control
- Verifiable Credentials (VCs) - Digital credentials you can prove are authentic
- DIDComm - Secure, private messaging protocol for DIDs
- Trust Triangle - The relationship between Issuers, Holders, and Verifiers
Learn more about Identus concepts →
Architecture & Building Blocks
Identus provides modular building blocks that can be combined for various use cases:
| Building Block | Code Name | Purpose |
|---|---|---|
| Cryptography | Apollo | Cryptographic primitives for data integrity and security |
| DIDs | Castor | Create, manage, and resolve decentralized identifiers |
| Verifiable Credentials | Pollux | Issue, manage, and verify credentials |
| DIDComm | Mercury | Secure peer-to-peer messaging protocols |
This modular architecture provides flexibility to customize solutions for specific requirements.
Development Workflows
Credential Issuance Flow
- Issuer creates a credential schema
- Issuer publishes a DID (for verification)
- Issuer sends credential offer to Holder
- Holder accepts and creates credential request
- Issuer issues credential to Holder
- Holder stores credential securely
Credential Verification Flow
- Verifier sends presentation request to Holder
- Holder selects matching credentials
- Holder creates and sends presentation to Verifier
- Verifier validates credential authenticity and issuer
- Verifier checks credential status (not revoked)
Connection Establishment
Agents establish secure DIDComm connections using:
- Direct invitations - For known parties with existing connections
- Out-of-Band (OOB) invitations - QR codes or deep links for new connections
- Mediator routing - Message delivery for offline/mobile wallets
Standards Support
Identus implements current W3C and DIF standards:
- ✅ W3C DID Core 1.0
- ✅ W3C Verifiable Credentials with JWT/SD-JWT
- ✅ DIDComm Messaging v2
- ✅ Hyperledger AnonCreds v1.0
- ✅ OpenID for Verifiable Credential Issuance (OID4VCI)
- ✅ OpenID for Verifiable Presentations (OID4VP)
- ✅ W3C Bitstring Status List v1.0
- ✅ DIF Presentation Exchange
View complete specifications →
API Reference
- Cloud Agent API - Complete OpenAPI specification
- TypeScript SDK API - Auto-generated API documentation
- Swift SDK API
- Kotlin SDK API
Example Applications
All SDKs include sample applications demonstrating end-to-end flows:
- TypeScript: React demo at
sdk-ts/demos/next - Swift: Wallet Demo in
identus-edge-agent-sdk-swift/Sample - Kotlin: SampleApp in
identus-edge-agent-sdk-kmm
Community & Support
- GitHub Discussions - Ask questions and share ideas
- Issue Tracker - Report bugs and request features
- Discord - Real-time community chat
- Contributing Guidelines - How to contribute to Identus
Additional Resources
- Architecture Decision Records - Understand key architectural decisions
- PRISM DID Specification - Deep dive into did:prism
- Security Policy - Security best practices and reporting
Ready to start building? Head to the Quick Start Guide to deploy your first Identus application!