Multi-stage document ingestion pipeline with email capture, structural validation, license/certificate verification, and XML extraction across six specialized hosts. Data flows from email inbox through capture, validation layers (structural, license, certificate, access key), status consultation, and front-end processing with database persistence. The architecture demonstrates a robust validation-first approach where each host handles distinct responsibilities: email reading, request reception, core validations, status queries, occurrence processing, and success tracking. Fork this diagram to customize validation rules, add error handling branches, or adapt for your document processing requirements. This pattern is ideal for compliance-heavy workflows requiring multi-point validation and audit trails.