Trust Registries

Trust registries define which issuers and keys are authorized to issue compliance proofs, enabling multi-issuer ecosystems and key rotation.

Purpose

A Trust Registry is a structured list of who is trusted to issue compliance proofs.

It provides a governance layer over issuers, roles, schemas, and revocations.

Trust registries answer:

• Which keys can sign Merkle roots or attestations?

• Which issuers are recognized for specific KYC levels or jurisdictions?

• How are compromised keys or outdated schemas revoked?

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Why They Matter

• Multi-Issuer ecosystems → more than one regulated entity can issue proofs.

• Key rotation → issuers can update or revoke signing keys without breaking dApps.

• Schema governance → define which compliance schemas are valid at a given epoch.

• Cross-chain consistency → same “who do we trust?” logic works for Cardano and EVM.

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Current State (MVP)

Fairway MVP runs in single-issuer mode:

• Fairway is the sole trusted issuer.

• DApps validate proofs by checking Fairway’s signature on:

  • Cardano: Merkle UTXO {root, epoch, midnight_ref}

  • EVM: EAS attestation under Fairway’s key

Trust Registry (today) = just the Fairway pubkey(s), hardcoded or stored in a simple on-chain datum for rotation.

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Future Roadmap (Planned Expansion)

Fairway will expand Trust Registries into a multi-issuer governance primitive:

1. Issuer List

   • Map of issuer addresses/keys → roles (KYC provider, accreditor, sanctions oracle).

2. Schema & Version Registry

   • Declare valid schema IDs for different compliance checks.

3. Revocation Epochs

   • Registry tracks when an issuer key or schema was revoked, ensuring dApps enforce freshness.

4. DAO Governance

   • Institutions stake Fairway token to onboard new issuers.

   • Curated by a governance process, not a single operator.

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Example: Future Multi-Issuer Registry

{
  "issuers": [
    {
      "address": "0xIssuerBank",
      "roles": ["KYC_L2", "Accreditor"],
      "schema_versions": [2,3],
      "revoked": false},
    {
      "address": "0xSanctionsOracle",
      "roles": ["SanctionsFeed"],
      "schema_versions": [1],
      "revoked": true,
      "revoked_epoch": 205
    }
  ],
  "last_updated": "2025-09-22T10:00:00Z"
}

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Diagrams

Evolution Path

flowchart LR
  MVP[Single Issuer: Fairway key] --> Phase1[Key rotation support]
  Phase1 --> Phase2[Multi-Issuer: banks, accreditors, oracles]
  Phase2 --> Phase3[DAO-governed Trust Registry with staking + curation]

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Benefits

• For Developers → stable pubkey source for eligibility checks.

• For Institutions → ability to recognize multiple issuers under governance.

• For Regulators → clear audit trail of “who was trusted when.”

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Roadmap Clarification

• MVP (2025) → single issuer, Fairway signature only.

• Mid stage (2026) → introduce Trust Registry module (multi-issuer).

• Late stage (2029) → DAO-governance and full decentralization ****

• Docs → early page included so developers and partners understand where Fairway is heading.

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Next Steps

• See Build on Cardano for how the current single-issuer signature is enforced.

• See Build on EVM for how attestations are verified today.

• Follow roadmap updates for when Trust Registry functionality ships.