Past Meetup

Disambiguating Aggregates / Event Storming

This Meetup is past

71 people went

RAMADA Hotel Berlin-Alexanderplatz (Room: "Grenader 3")

Karl-Liebknecht-Str. 32 · Berlin

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Disambiguating Aggregates

Of all patterns in Domain-Driven Design, Aggregates vs Aggregate Roots vs Aggregate Boundaries seem to be the most confusing. Can we clean up the naming? Can we move away from defining Aggregates from a structural point of view, and see them as managing business processes instead, using lifecycles and constraints as our primary heuristics? What tradeoffs do we need to make? How similar or different are Aggregates in Object Oriented models, in Event Sourced models, and in Actor Model? This session is an open exploration of one of the most powerful ideas in tactical DDD.


Mathias Verraes is a programmer, consultant, blogger, and trainer. He advises companies on building enterprise applications for complex business domains, and on dealing with legacy systems. He has advised for clients in Automotive, Government, Logistics, Finance, E-Commerce, and more. He teaches Domain-Driven Design courses and co-organises the DDD Europe conference. When he’s not working, he’s at home in Kortrijk, Belgium, helping his two sons build crazy Lego train tracks.


Event Storming

Why spend an eternity on analyses and planing, when you could be creating a complex domain model within a few hours. How do you create a vivid picture of your business processes, without beeing stuck in endless meetings? How do you tackle all that complexity and how do you even begin with modelling?

Event Storming combines agile modelling practices and the (not all that) new event driven approach in a way, that enables collaborative exploration of the problem domain. As a result you quickly get a clear modell, created and shared by everyone involved. This way you get early feedback on friction and misunderstandings.

Marco Heimeshoff will show you in this talk, how you can create implementation friendly models with joy and ease, and a little love for colorful post-its.

Speaker: Marco Heimeshoff