> For the complete documentation index, see [llms.txt](https://docs.fairway.global/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fairway.global/developers/core-concepts/trust-registries.md).

# Trust Registries

### 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* *How are compromised keys or outdated schemas revoked?*

***

### 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.

***

### 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.

***

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   * Registry tracks when an issuer key or schema was revoked, ensuring dApps enforce freshness.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

***

### Example: Future Multi-Issuer Registry

```json
{
  "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"
}

```

***

### Diagrams

#### Evolution Path

```mermaid
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]

```

***

### 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.”

***

### 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.

***

### Next Steps

* See [Build on Cardano](https://docs.fairway.global/~/revisions/LmhbGZ8szY6vRl5kdqPa/developers/build-on-cardano) for how the current single-issuer signature is enforced.
* See [Build on EVM](https://docs.fairway.global/~/revisions/LmhbGZ8szY6vRl5kdqPa/developers/build-on-evm) for how attestations are verified today.
* Follow [roadmap](https://docs.fairway.global/~/revisions/LmhbGZ8szY6vRl5kdqPa/developers/changelog-and-roadmap) updates for when Trust Registry functionality ships.