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Event Modeling

Visual notation for flows, commands, events, and read models

Practice

A whiteboard notation linking user journeys, commands, domain events, and read models in one diagram — designed for implementable event-driven systems.

MARKO ŽIVKOVIĆ In review

Event Modeling is a visual design practice for event-driven systems. A single diagram connects what the user sees (screens and queries), commands they trigger, domain events that record what happened, and read models that answer queries — with explicit flow order and causality.

The method name follows the official American spelling used at eventmodeling.org. Elsewhere on this site, generic verbs keep British modelling (e.g. “modelling events”).

The notation was developed by Adam Dymitruk, published and taught through eventmodeling.org and related workshops.

What it is

Unlike a flat event list, Event Modeling keeps behaviour and UX in the same picture as the event log:

  • Wireframes / views — what the actor reads.
  • Commands — intentions that may fail or succeed.
  • Events — past-tense facts appended when something actually happened.
  • Read models — projections built from events to serve the next view.

The model is implementation-oriented: it is meant to translate directly into services, handlers, and projection code without re-deriving structure from CRUD tables.

When to use it

  • After discovery (often following Event Storming) when the team needs a buildable blueprint.
  • When explaining event-driven design to product and engineering on one canvas.
  • When separating append-only substrate from projection storage — read models and views are explicit, not an afterthought of SELECT from the write table.

Relation to this site

Event Modeling supports domain events name the real world: events on the diagram should use business verbs, while read models may legitimately use CRUD at the projection boundary. Pair with Domain Events Are Not CRUD and the CRUD as domain language anti-pattern when reviewing whether diagrammed events have collapsed into generic Created / Updated labels.

Further reading