Event Sourcing

Kind: pattern

Layer: Execution Core

Record: architecture:event-sourcing

Severity: contextual

Scope: domain, persistence

Canonical: Ontology

A design pattern that stores state as the sequence of events that produced it and rebuilds current state by replaying them.

Listed in Architecture principles, after Event Stream and before Command Query Responsibility Segregation (CQRS).

Requires

• Append-Only Log
• Domain Events

Reinforces

• Auditability
• Temporal Modeling

Enables

• Replay
• Replay

Conflicts with

• CRUD-Only State Persistence

In tension with

• Query Complexity

Tensions

• Event Sourcing / Query Complexity

Violated by

• CRUD-Only State Persistence

Refactored by

• Query Projection

Severity

• contextual

Category

• Event / Messaging / Asynchronous Architecture

Enabled by

• Event-Driven Architecture

Reinforced by

• Command Query Responsibility Segregation

Linked from

• Coordination is software
• Every record has a kind
• Execution joins the halves
• Event / Messaging / Asynchronous Architecture
• Observability / Auditability / Traceability
• Core Vocabulary
• Event Messaging Async
• Severity levels
• The resolutions