Yivi’s core mechanism is not generic self-sovereign identity. It is an Idemix-based attribute-credential stack where issuers sign attributes, users hold credentials locally, and verifiers receive selective-disclosure proofs instead of raw identity documents or complete profiles.
The scheme-manager layer is the most analytically important control surface. The schemes docs explicitly say the scheme manager signs and distributes issuer metadata, issuer public keys, credential definitions, and optional keyshare configuration, and has exclusive control over which issuers and credential types enter the scheme.
The technical overview is especially valuable because it shows how holder-binding works without exposing a global public identifier: each credential includes the same hidden holder secret as its first attribute, so a verifier can learn that multiple credentials belong to one holder without learning the secret itself.
The keyshare server adds a second important layer that many newer identity-wallet pitches hide. Yivi explicitly trades some decentralization and some privacy for stronger device/PIN binding, brute-force resistance, and remote blocking by splitting the holder secret between the wallet and a cooperating online service.
The docs make clear that Yivi is more than disclosure/login middleware. Attribute-based signatures are a distinct export surface where a user signs a message together with verifiable credential facts.
The current EUDI roadmap is important because it shows Yivi as a live migration case, not just a historical system. The team says the existing Idemix-plus-IRMA stack is mature and privacy-preserving but now needs crypto agility, multi-trust-scheme support, and OpenID4VP/OpenID4VCI interoperability.
The public GitHub organization and irmago README reinforce that Yivi is a full ecosystem rather than a single app: mobile wallet, server, keyshare flows, frontend packages, scheme tooling, and issuer/verifier infrastructure are all first-class components.
Specific source signals worth retaining
What is Yivi? is the cleanest source for the requestor / IRMA-server / wallet session flow and for the three main session types: disclosure, issuance, and attribute-based signatures.
Technical overview is the best source for the deeper architecture: participant roles, credential structure, metadata attribute, shared hidden holder secret, and the privacy properties of selective disclosure.
Schemes is the best source for the scheme-manager control plane, signed directory distribution, issuer admission, credential-type definition, and keyshare-server configuration as a trust-scheme layer.
Keyshare protocol is the best source for the explicit tradeoff around split-secret device binding, PIN enforcement, SE/TEE-backed challenge signing, and remote blocking.
The 2025 EUDI-wallet roadmap is the best source for why Yivi still matters now: it documents the pressure to move from a mature proprietary privacy stack toward interoperable VC and trust-scheme standards without abandoning privacy goals.
Why this entry belongs in the corpus
It gives the corpus a strong historical and architectural baseline for privacy-preserving credential systems that predates many current wallet and zk-passport brands while still remaining operationally current.
It strengthens the identity cluster by separating credential cryptography, issuer admission, trust-scheme custody, device-binding, and verifier-session transport into explicit layers.
The durable insight is that many modern identity wallet systems quietly bundle together at least five separable control planes: credential issuance, credential-catalog governance, holder binding, proof transport, and interoperability standards. Yivi keeps those seams unusually visible.