Build your own validator
Validators are a core component of the Fabrica ecosystem, responsible for verifying property claims, maintaining NFT good standing, and providing metadata services. Third parties can build their own validators to serve specific geographies, property types, or compliance requirements.
Validator Responsibilities
A validator must provide the following core functions:
- Property Validation: Verify that the NFT claim matches recorded property documents at the relevant jurisdiction
- Metadata Generation: Provide current metadata for property tokens, aggregating data from multiple sources
- Confidence Scoring: Calculate and maintain confidence scores based on validation checks
- Compliance Monitoring: Ensure ongoing compliance with local regulations and reporting requirements
Technical Requirements
Smart Contract Interface
Validators implement a smart contract that conforms to the Fabrica validator interface (IFabricaValidator). The onchain interface is intentionally small, a metadata and operating-agreement resolver, not a transfer gate:
defaultOperatingAgreement(), the validator's default operating agreement URIoperatingAgreementName(uri), a human-readable name for a given operating agreementuri(tokenId), the token metadata URI the validator serves
The validator's address is recorded on each token and resolved to a name through the Validator Registry. Validation, scoring, and any approve/reject decisions happen in the validator's off-chain services (below); the protocol does not call the validator to gate a holder's transfers.
Required Services
Validators typically need to provide:
| Service | Description |
|---|---|
| Metadata API | Serve NFT metadata following standard conventions |
| Media Server | Generate dynamic images/animations representing properties |
| Scoring API | Return confidence scores and validation check results |
| Valuation API | Provide property value estimates from third-party sources |
Validation Checks
At minimum, validators should perform these validation checks:
- Proof of title verification
- Legal description matching
- Holding entity verification
- Owner KYC/AML status
- OFAC/sanctions screening
- Coordinate validation
See the Validation Process documentation for details on how these checks contribute to confidence scoring.
Integration with Fabrica
To integrate your validator with the Fabrica ecosystem:
- Deploy your validator smart contract
- Register with the Validator Registry
- Implement the required API endpoints
- Pass Fabrica's validator certification process
Get Started
Building a validator requires technical expertise in blockchain development, real estate title processes, and compliance systems. Contact us at [email protected] to discuss your validator project and receive guidance on the certification process.