> ## Documentation Index
> Fetch the complete documentation index at: https://docs.coverfi.space/llms.txt
> Use this file to discover all available pages before exploring further.

# Registry Contracts

> Username and receipt registry contracts

CoverFi includes registry contracts alongside the protection engine and vault system.

## `username_registry`

Maps a human-readable CoverFi username to a Stellar wallet address. This supports executed username payments and user discovery.

Key readiness checks:

* Enforce username format and length.
* Prevent duplicate registrations.
* Require user authorization for registration or updates.
* Reject reserved names.
* Enforce lowercase username rules.
* Support renewal, release, reverse lookup, and availability checks.

Username payment sequence:

```mermaid theme={null}
flowchart LR
  A[Sender enters username] --> B[Registry get_address]
  B --> C[App builds Stellar payment]
  C --> D[Sender wallet signs]
  D --> E[Stellar confirms payment]
  E --> F[Optional receipt hash anchor]
```

## `receipt_registry`

Stores optional paid payment receipt records created after wallet-signed payments and combines the previous receipt access, anchor, and dispute surfaces.

Current controls:

* Owner authorization for receipt creation.
* Canonical receipt hash and reference hash anchoring.
* No duplicate receipt creation for the same receipt hash.
* Individual receipt-print fees route to the configured treasury wallet for the current MVP.
* Only the receipt owner can grant access.
* Revocation is tested.
* Merchant-signed batch anchoring.
* Batch count and root validation.
* Immutable historical anchors.
* Prevent unauthorized dispute mutation.
* Store clear status transitions.
* Keep personally sensitive data off-chain.

Remaining limitation:

* The registry stores a receipt proof hash, but it cannot independently prove that the referenced Stellar payment settled. The app/backend must verify settlement before offering paid receipt printing.