Decentralized Identity and Zero-Knowledge Proofs

Description Data breaches and centralized control have fractured digital trust. This book bridges that gap by exploring self-sovereign identity (SSI), decentralized identifiers (DIDs), and zero-knowledge proofs (ZKPs) as approaches to digital identity, privacy, and trust. Beginning with the evolution of digital identity systems, the book establishes SSI principles, trust models, and decentralized identity before moving into DID methods, verifiable credentials, verifiable presentations, and DID authentication. It then builds the foundations of ZKPs through cryptographic foundations and proof systems, progressing to zk-SNARKs, zk-STARKs, circuit development using Circom and snarkjs, and advanced techniques such as recursive proof composition, lookup arguments, folding schemes, and ZK-rollups. The book then brings DIDs and ZKPs together through privacy-preserving credentials, selective disclosure, predicate proofs, and practical protocols. By the end of this book, you will be fully equipped to architect, code, and deploy production-grade, privacy-preserving identity solutions, transforming how your organization manages trust, user privacy, and compliance. What you will learn Architect self-sovereign identity systems using W3C DID standards. Design and optimize ZK circuits using Circom and snarkjs. Implement selective disclosure and predicate validation protocols. Deploy robust cryptography including Pedersen commitments and Merkle trees. Build anonymous KYC and voting application workflows. Scale decentralized identity frameworks securely. Protect AI models with zero-knowledge proofs. Who this book is for This book is for blockchain engineers, security architects, privacy engineers, and full-stack developers looking to build next-generation identity solutions. It is ideal for software professionals aiming to master cryptographic proofs and decentralized trust networks. Table of Contents 1. Identity Crisis and Importance of Privacy 2. DID Core Concepts and Standards 3. DID Implementation 4. Zero-Knowledge Proof Fundamentals 5. Cryptographic Foundations for Zero-Knowledge Proofs 6. ZKP Proof Systems and Frameworks 7. Developing ZKP Circuits and Proofs 8. Advanced Topics in ZKP Systems 9. Integration Architecture and Design Patterns 10. Privacy-preserving Credentials 11. Advanced Integration Projects 12. Zero-Knowledge Machine Learning 13. Production Deployment and Scaling 14. Emerging Trends and Future Directions