Astucia internal mail · transactional
Email that leaves a paper trail.
RelayFlow is the house transactional email service — a drop-in HTTP API with a ledger of every message, delivery event, and suppression.
Drop-in HTTP API
A documented REST surface with bearer keys — the /emails API, batch sends, and idempotency keys work as expected.
Every send on the record
Full envelope, delivery events, and provider IDs for each message, kept in one ledger you can search and audit.
Suppressions enforced
Hard bounces and complaints are stamped once and never mailed again. Manual blocks take one form field.