Bio

Dagmar de Haan has been working as an IT architect at MaibornWolff in Frankfurt since 2014. Since her beginnings in software development a good 20 years ago, she has been concerned with the question of what makes good software, how it is created and above all how it is preserved.

Her main interests include

- Agile software development
- Design pattern
- Clean code
- Software reengineering
- TDD
- Voice control with Alexa

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Discovering Aggregate Implementation Patterns via "Code Koans" (Lab)
by Anton Stöckl, Dagmar de Haan

There are many ways to implement the Aggregate pattern from Domain-Driven Design:

* OOP style or functional style
* traditional or event-sourced
* inline state, external state, on-the-fly state (reconstitute inside the aggregate)
* reconstitute the full state or just the minimal state needed to make decisions
* recording changes or returning changes

We will discover as many of those variations as possible during the workshop.

Attendees will implement different variations of the same Aggregate in a "Code Koans" like fashion. For each variation there will be test cases and a skeleton which has to be filled with the missing code to make the tests green. We will supply a repository with Java Code.