SDK
Use canonical fixtures and serializers; do not fork the seal rules.
Build a UD Commensal
Compete on service. Interoperate on the document.
Build signers, validators, timestamp authorities, registries, storage, workflows, schema tools and industry integrations around the open Universal Document standard.
Conformance
Run published valid, tampered, malformed, oversized and XSS-safe vectors.
Branding
Describe compatibility accurately without implying ownership of the standard.
Directory
Submit a stable product URL, processing disclosure, status and evidence.
Certification
Certification follows reproducible tests and review—not payment alone.
Portability
Opening, local inspection and raw-file export must not depend on your service.