Sismo

• Name: Sismo
• URL: https://docs.sismo.io/
• Category: privacy-preserving identity-and-attestation middleware / zero-knowledge SSO / data-group proof infrastructure / badge protocol
• Tags: ethereum-ecosystem
• Summary: Sismo is private account-binding and eligibility-proof middleware. The useful split is between the local Data Vault, the trusted Commitment Mapper, Data Group root publication, and the issuer-controlled badge layer. Keep it as a note on group-proof plumbing, not a catch-all zk identity bucket.
• What it does:
  • Lets users aggregate wallets and supported web2 accounts inside a private local Data Vault and generate zero-knowledge proofs from that vault
  • Offers Sismo Connect so apps can request proofs of account ownership, group membership, or app-specific anonymous identifiers (vaultId)
  • Defines Data Groups as sets of supported accounts plus associated values, then publishes Merkle roots for later proof verification
  • Runs Sismo Hub / Factory flows for group generators, data providers, groups, badge metadata, and app integrations
  • Uses a Commitment Mapper service to turn account-ownership proofs into SNARK-friendly commitment receipts
  • Stores attestations in an onchain registry while exposing badge balances through a stateless non-transferable ERC-1155 view
• Key claims:
  • The reusable primitive is not identity in the abstract. It is the split between private account aggregation, commitment translation, group construction, and governed attestation issuance.
  • The Data Vault makes Sismo distinct from issuer-first attestation systems because the stack begins with private account aggregation rather than a public credential object.
  • vaultId is the clean comparison point: app-specific uniqueness without a globally public identifier.
  • Commitment Mapper is one of the real choke points. Sismo’s own docs treat it as a trusted offchain service, so the privacy story still inherits intermediary trust.
  • Group generation is another control layer. Whoever defines generators, selects data providers, and publishes roots has a large say in what eligibility means.
  • The badge layer is thinner than it looks. The registry is public, but issuer authorization and collection control still decide what gets written.
  • Sismo belongs in the active corpus because it cleanly separates private account binding, trusted ownership translation, reusable group roots, app-specific uniqueness, and badge issuance.
• Whitepaper: No canonical standalone Sismo whitepaper or litepaper surfaced in this pass. The strongest primary materials were the official docs README, the Data Vault / Data Groups / Commitment Mapper docs, the Sismo Hub README, and the protocol contracts repository. See ../whitepapers/sismo-primary-sources-2026-05-10.md.
• Sources:
  • https://docs.sismo.io/
  • https://github.com/sismo-core/sismo-docs
  • https://raw.githubusercontent.com/sismo-core/sismo-docs/main/README.md
  • https://raw.githubusercontent.com/sismo-core/sismo-docs/main/data-vault/what-is-the-data-vault.md
  • https://raw.githubusercontent.com/sismo-core/sismo-docs/main/data-vault/commitment-mapper.md
  • https://raw.githubusercontent.com/sismo-core/sismo-docs/main/data-groups/data-groups-and-creation.md
  • https://github.com/sismo-core/sismo-hub
  • https://raw.githubusercontent.com/sismo-core/sismo-hub/main/README.md
  • https://github.com/sismo-core/sismo-badges
  • https://raw.githubusercontent.com/sismo-core/sismo-badges/main/README.md
  • https://raw.githubusercontent.com/sismo-core/sismo-badges/main/contracts/core/AttestationsRegistry.sol
  • https://github.com/sismo-core/sismo-commitment-mapper

Internal linkages

• Best upward reads: world-id, human-passport, and self-protocol.

Control surface

• The real choke points are Commitment Mapper operation, group-generation policy, issuer admission, and the app defaults around vaultId or badge sufficiency.

• That is why this note belongs on proof middleware, not on generic zk identity vibes.

• Last reviewed: 2026-06-15 UTC