From EventStorming to CoDDDing @ JFall

To really understand what our users need so that we can build the right thing, we want to have a first-hand experience of ‘real-life stories’ before we model and create our software. To quote Alberto Brandolini “it is not the domain expert’s knowledge that goes into production, it is the developer’s assumption of that knowledge that goes into production”. EventStorming is a visual technique that minimizes assumptions by engaging in collaborative deliberate learning across different disciplines. This helps to solve complex business problems in the most effective way.

Although the learning of the domain helps us to understand the domain better, EventStorming can be quite an overwhelming experience. Developers can be left with the question of how to turn a few stickies on a wall into working code.

Join us in this talk in which we show the basic principles of EventStorming. We will cover the different forms of EventStorming and in which situation they best can be applied. And, we will show how you can leverage DDD (Domain-Driven Design) patterns in an EventStorming software modelling session that will ultimately result in coding TDD (Test Driven Development) style!

Transcript

1. From EventStorming
   to CoDDDing
   

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2. Software Consultant - EventStormer
   Domain Driven Design
   Behaviour Driven Development
   Test Driven Development
   Continuous Delivery
   @kenny_baas
   baasie.com
   @joaoasrosa
   joaorosa.io
   

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9. The fundamental horror of this anti-pattern
   is that it's so contrary to the basic idea
   of object-oriented designing;
   which is to combine
   data and process together.
   - Martin Fowler
   

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10. What's worse, many people think that
    anemic objects are real objects,
    and thus completely miss the point of what
    object-oriented design is all about.
    - Martin Fowler
    

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14. Confirmation Bias
    

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15. https://lizkeogh.com/2015/09/09/on-epiphany-and-apophany/
    Build beliefs
    Draw conclusions
    Generate assumptions
    Filter data
    Observe data
    

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16. It is not the domain experts knowledge
    that goes to production, it is the
    assumption of the developers
    that goes to production
    - Alberto Brandolini
    

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17. The greatest obstacle to discovery is not ignorance -
    it is the illusion of knowledge.
    - Daniel J. Boorstin
    

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18. To communicate effectively, the code must be based on
    the same language used to write the requirements
    - the same language that the developers speak
    with each other and with domain experts
    - Eric Evans
    

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19. We all know or should know that language is fluid, liquid, subject to the
    whims of the people. Language evolves, as it should. Because language
    changes to accommodate new users, the older users resist and complain.
    http://tednellen.blogspot.com/2013/04/language-is-fluid.html
    

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25. Big Picture
    Process Design
    and Modelling
    Software
    Modelling
    

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32. 1. Protects business invariants
    2. Design them small
    3. Reference other by ID only
    4. Update other using eventual
    consistency
    

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33. Try at least to find three models,
    even if you think you already found
    the “right model”
    

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36. Software Development is
    a learning process, working code is a
    side effect
    - Alberto Brandolini
    

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37. Serious software development is
    the practice of symmathesy.
    “Sym” = together, “mathesy” = learning.
    - Jessica Kerr
    

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38. #CatTax
    

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