Signature Providers

Sign Relay supports multiple electronic signature providers through a unified interface.

Currently Supported

D4Sign

Brazilian electronic signature provider with advanced features including:

• Digital certificate support (ICP-Brasil)
• Multiple signer workflows
• Document templates
• Advanced security features

Provider Interface

All providers implement the same interface, making swapping seamless:

interface SignatureProvider {
  createDocument(request: CreateRequest): Promise<Document>;
  getStatus(id: string): Promise<Status>;
  parseWebhook(payload: unknown): Promise<WebhookEvent>;
}

Adding a New Provider

To add a new provider:

1. Create a new adapter in src/adapters/
2. Implement the SignatureProvider interface
3. Add provider configuration
4. Write tests for the adapter
5. Update documentation