Records, sealed outcomes, SPIs and the rule document model. Zero dependencies.

Rule compiler, pure resolver, engine, registry with tenant overlays, in-memory store and transport, Mermaid renderer.

Jackson codec for the envelope and audit records, shared by every transport and store that serialises them (H10: an event must stand on its own).

YAML/JSON rule set parser (DD-04) and file/classpath definition sources (DD-05).

Optional tasks module over the event mechanism (DD-10): stores lifecycle.task.create notifications as tasks and raises the deferred onComplete signal.

JDBC backend (DD-07, DD-11): state, inbox, audit and outbox in one transaction on a plain DataSource, plus a stored rule set source and a task store.

MongoDB backend (DD-07, DD-11): state, inbox, audit and outbox via mongodb-driver-sync, with a single multi-document transaction on a replica set and a documented single-document fallback for a standalone server, plus a stored rule set source ...

Kafka transport (DD-08, DD-09, DD-11): per-entity ordering by partition key, redelivery with a dead-letter topic, no delayed delivery.