essay · process
Event Storming to 100% alignment
The most expensive bug in software isn't in the code — it's in the shared understanding of the people building it. Business says "fast claims", tech hears "cache everything", and six months later everyone is surprised. Event Storming is the cheapest fix I know: one room, a wall of sticky notes, and the whole system on the table in an afternoon.
Here's how it works, and why it keeps landing at 100% business–tech alignment.
The room
Domain experts, product, engineering — everyone who touches the process. No slides, no pre-reads. The domain experts talk; the engineers listen and ask. The rule that makes it work: events first. Orange notes, past tense. "Submission received", "risk score computed", "policy bound".
Once the events are on the wall, the chaos starts organising itself. Commands, read models, and business rules get pinned next to the events they connect. 5–10 new ideas per session is normal — ideas that had never survived the journey from business brain to backlog.
events → clusters → bounded contexts: the architecture falls out of the conversation
Why it beats every kickoff meeting
Because the wall doesn't lie. In a slide deck, disagreements hide in the margins. On the wall, they're visible contradictions — two events in impossible order, a rule nobody wrote down, a domain expert going "wait, that's not how it works". Hidden complexity surfaces early, when it costs a sticky note instead of a sprint.
The second win is the boundaries. Clusters of related events become natural bounded contexts — and bounded contexts become service boundaries. We never argue about where a service starts; we point at the wall.
Alignment as a side effect
By the time the session ends, business has seen their whole operation on a wall, tech has seen their whole system before writing a line of code, and everyone agrees on what "done" means. That's the 100%: not a vote, not a sign-off — a shared picture nobody can unsee.
Alignment before architecture. The architecture falls out of the conversation — and the conversation is the deliverable.