The World's Shortest and Most Chaotic Introduction to Event Storming

CukeUp London April 2016
http://verraes.net

Transcript

1. The World's
   Shortest and
   Most Chaotic
   Introduction to
   Event Storming
   @mathiasverraes @jbpros
   

   View Slide

2. Mathias
   Verraes
   Independent Consultant
   @mathiasverraes
   verraes.net
   

   View Slide

3. Julien
   Biezemans
   Co-founder at Cucumber
   @jbpros
   

   View Slide

4. View Slide

5. The Grand Dichotomy of Systems1
   Things vs Processes
   1 "Rethinking System Analysis and Design" — Gerald M. Weinberg
   

   View Slide

6. Event Storming:
   visually modelling
   behaviour over time
   

   View Slide

7. Today:
   Big Picture
   Event Storming
   Exploration — Ubiquitous Language — Processes
   

   View Slide

8. Going further:
   Design Level
   Event Storming
   Precision — Constraints — Processes
   Dependencies — Messaging — Event Sourcing
   Bounded Contexts — Concurrency — Race Conditions — ...
   

   View Slide

9. View Slide

10. Domain Event
    Something has happened in the past
    that is relevant to the business
    Past tense: Trip has Started
    

    View Slide

11. Command
    An instruction that a user (or another system) sends
    to your system
    Imperative: Start Trip
    

    View Slide

12. Business Rule
    A constraint that determines the outcome (Events) of
    a particular Command
    

    View Slide

13. Given there is a user
    vs
    Given a user has registered
    Given Event
    And Event
    When Command
    Then Event
    

    View Slide

14. @mathiasverraes
    verraes.net
    

    View Slide