Event Sourcing For Product Teams

Plain-English Explanation

Most systems store the latest state: the current order status, account balance, claim stage, or appointment time. Event-sourced systems store the facts that led there: Order Placed, Payment Authorized, Order Packed, Order Shipped.

The generated system can rebuild current views from those events and keep a history of how the state changed. Users do not need to understand event stores, snapshots, rehydration, or projection infrastructure to model the important behaviour.

Why Use It

• Audit history is a first-class need.
• The business asks “how did we get here?” as often as “what is the current state?”
• Events are useful for integration, analytics, compliance, or customer support.
• The system needs to rebuild or add new read models from past behaviour.
• The domain has meaningful lifecycles, not just editable records.

Where It Fits In Code Genie

When an aggregate accepts a command, it can produce one or more domain events. In an event-sourced generated system, those events become the durable record of what happened. Read models are built from events so users still get fast screens, lists, dashboards, and reports.

Good Event Examples

• Insurance: Claim Opened, Evidence Requested, Assessment Completed, Claim Approved, Payment Issued.
• Healthcare: Referral Received, Appointment Scheduled, Triage Completed, Care Plan Updated.
• Commerce: Cart Checked Out, Payment Authorized, Inventory Reserved, Shipment Dispatched, Return Received.
• SaaS: Subscription Started, Seat Added, Payment Failed, Plan Changed, Subscription Cancelled.

When Not To Select Event Sourcing

Use a simpler persistence style for simple reference data, low-value audit trails, or systems where every change is just an edit to a record. Event Sourcing is powerful when events are meaningful to the business. If the team cannot name meaningful events, the system may not need it.