Earlier this week I was excited and had the pleasure of taking part in "semi" organizing an event storming session. It was my first time but there will definitely be more. In fact, we are planning on doing more of these sessions and we took this first session as a practice run. As a way to let people in the organization take part and learn about the format. Preparations were made so that we had a room where tables and chairs had been pushed aside (no sitting). We had covered the walls with papers from a really long paper role. Multiple sets of coloured Post-its was acquired so that we could represent the different artefacts: events, commands, external "triggers" or triggers by time, annotations and roles.
The right number of people
We "intentionally" invited more than the recommended number of 6-8 persons and I can definitely understand why you should not exceed that number. I think we doubled it. We had two walls covered with papers where we could hang our Post-its and luckily we were two facilitators and could therefore try and cover one "sheet" each, but even so it was really hard to be able to facilitate. But I'm super impressed on how many events came up in that small amount of time. It was around 20 minutes of effective time for people to interact and discuss and to produce events.
Summary: Keep the maximum size around 6-8 people.
Set the scene
In the invite as well as initially a small intro of why and how was given. We also tried to emphasize on what to focus on first, the business events. Doing this as an exercise, this is where I probably will stop the next time. And not mention the other artefacts like commands. Not until we all together have identified some of the business events and are ready to proceed on the next step.
Summary: Baby steps. Don't give too much info so that people advance in beforehand. Although, this will probably be easier to handle if the crowd is smaller.
Choice of domain
The domain that we focused on was taken from the domain where we all work in. Now, this was probably part of the reason why so many events were produced, but we also saw this as a risk. A risk that the different opinions of the domain took too much time and energy so that we didn't get that far in the event storming session that we wanted.
Summary: If for exercise purpose, then use a small and preferably easy domain and be prepared to provide "samples".
In retrospect, my feeling is:
Let's do it again! And again!
I looked at the event and given that it was a bit chaotic I'm super impressed by the result that was produced. I'm eagerly waiting for the next session. Where we can have a smaller group. Have more focused discussions and reach further in the process.
A small tip. Have a retrospective on what to improve upon. I guarantee that attendees have other opinions than facilitators.