DomainEvent

Represents a domain event published by an aggregate in response to a command.

Domain events capture significant business occurrences that have happened within an aggregate. They are immutable facts about past actions and serve as the primary mechanism for communicating state changes to other parts of the system.

Domain events follow declarative design principles (idempotent, similar to Kubernetes apply or Docker image layers). During event sourcing, aggregates should simply apply domain events as overlay layers without complex logic or conditional checks, eliminating the need for explicit sourcing functions.

Key characteristics:

• Immutable: Events represent facts that cannot be changed

• Named: Each event has a specific business meaning

• Versioned: Events carry version information for compatibility

• Sequenced: Events maintain order within an aggregate's lifecycle

Type Parameters

See also