Combining Domain Driven Design and Behaviour Driven Development

In my previous post, I discussed why we want to write software with empathy in mind; software that is understandable for peers. For us to create software with empathy in mind, we need to create a shared understanding of the users' needs; the needs we are trying to satisfy with our software. Practices like Domain Driven Design (DDD) and Behaviour Driven Development (BDD) can help us achieve this. By using Feature Mapping (a technique from BDD) and improving this with Event Storming (a technique from DDD), we can create executable specifications and a model for our business needs at the same time. This way, we can write software and tests that match the shared understanding the business has, which enables us to ship more value faster.

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An Ubiquitous Domain language throughout testing

One of the biggest challenges as engineers is to write working software and also keep an extensive documentation. Most engineers hate writing documentation, and after they published documentation on a wiki it will die a lonely death. We want to strive for writing a Living Documentation in an Ubiquitous Language. Practices like Domain Driven Design (DDD) and Behaviour Driven Development (BDD) can help you achieve this. Especially when we start writing code, it is really important for the quality of our software to start with tests describing what your application does. We want to write software with empathy in mind, software that is understandable for peers. While software developers are beginning to use the language of the domain (business language) more in their application code, most tests still contain a lot of technical language.

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Property-based testing in Java with JUnit-Quickcheck - Part 1: The basics

To be able to show you what Property-based testing (PBT) is, let's start by grasping the concept of a property in programming languages. Since this is a Java tutorial, I will start with Oracle and their definition of a property in their glossary:

Characteristics of an object that users can set, such as the color of a window.

Property is neither a variable/field or a method; it is something in between which is always true in your context. An example is weight in a postal parcel: this always is greater than zero.  In Java the following example implementation would follow:

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