Verifiable Credentials & DIDs

"Verifiable Credentials & DIDs: Wallets, OIDC Flows, SD‑JWT, and Secure Messaging"
Verifiable Credentials are moving from lab demos to regulated, adversarial production environments—and the engineering bar is rising accordingly. This book is written for experienced architects and senior developers who need more than vocabulary: a coherent mental model of issuer–holder–verifier systems, clear trust boundaries inside real wallets, and a threat baseline that survives phishing, replay, misbinding, and correlation pressure.
You will learn to implement and harden the core standards that now define the VC ecosystem: W3C VCDM v2.0 semantics, DID Core and trustworthy resolution, JOSE validation discipline, SD‑JWT (RFC 9901) selective disclosure, and the industrial issuance and presentation flows of OpenID4VCI and OpenID4VP. The focus stays practical: building deterministic wallet pipelines, designing minimal-disclosure requests, performing verifier-side validation from JOSE checks through domain policy, and operating issuer infrastructure with key rotation, auditability, and compromise response.
Coverage also extends beyond redirects into real product workflows: DIDComm v2 secure messaging patterns, mediator routing hygiene, hybrid OIDC+messaging channel binding, and the emerging W3C Digital Credentials API with browser-mediated origin constraints. Readers should be comfortable with modern cryptography and OAuth/OIDC concepts; the differentiator here is depth, trade-off clarity, and an implementation-first approach to security and privacy.