A domain event names something significant that happened in a business domain. In EventStorming, participants write events in the past tense on orange sticky notes and arrange them roughly from left to right. Each note marks a point in time; “Review Published,” for example, identifies when a review became visible. The simple notation lets people across business and technical roles contribute without first learning a detailed modeling language. section 7.0 section 7.1.1
Start with what matters to the business, wherever it happens:
- A customer interacts with a product: “Review Added.” section 7.1.1
- Something happens in a customer’s life outside the product: “Thought About Moving Home.” section 7.1.1
- A person or software acts within the organization: “Claim Approved” or “Driver Selected.” section 7.1.1
When building a timeline, put plausible events on the wall first and refine them together later. Seed a few events across the process, leave space for missing steps, and allow branches where scenarios differ. Do not demand a tidy diagram too early. For detail, tell a specific story rather than compressing a complex process into a few generic events. Prefer domain outcomes to mechanics such as “Submit Button Clicked” or “Item Saved to Database”; the useful level of detail depends on the question the group is exploring. section 7.2.4 section 7.4.1 section 7.5
From a mapped event to a workflow
In a contract-approval workflow, a salesperson requests approval from a system. The system produces “Contract Approval Requested,” which activates a policy to request legal approval. This is a more constrained use of the notation than an open-ended, big-picture timeline: a system produces the event after receiving a command. section 8.4.1
A domain event can also be produced by software, not just written on a workshop note. During a gradual modernization, new bounded contexts published “Job Published”; an anticorruption layer intercepted that event and translated it into the legacy job model. The shared event name connects the business occurrence to an integration decision, but a workshop timeline alone does not prescribe that implementation. section 12.5 section 7.1.1
