Seven kinds of bad taste information in domain modeling

Domain modeling (see sidebar) as a powerful technology, is standing in the toolbox of many IT pros. Unfortunately, in the past few years, there have been several problems with domain modeling that have led to disappointment, especially in the field of agile. The two real problem with this approach is that it takes too long and can easily lead to "analytical paralysis (analysis paralysis"), which leads to stagnation ("Spinning wheels"). We provide a way to model domain modeling that can be used to solve these problems.

We will discuss some of the signals in the domain model that will tell you to ask more questions. We call these signals "bad taste information" (information smells), and they remind us that we may not fully understand the information that the domain model is concerned about. These bad smells may mean that we lost information in our domain model or that the domain model contains incorrect information. Focusing on bad taste information leads us to the question that needs to be answered, which is a quick process. When all the bad smells are gone or we can confirm that the rest is acceptable, we stop, which prevents analysis from being paralyzed.

This process begins with the output of the system, which delivers value to the user. We do not explain how to find this value in this article. (We'll discuss this in a later Infoq article, "Introduction to Domain modeling.") Next, we process the bad taste information in the model based on the output.

To illustrate the bad taste of the information in this article, we'll use a virtual example that comes from multiple real-life scenarios. Our HR executives want to know how the salaries of various developers are paid, so that they can avoid the legal disputes that result from unjust payments between different groups of people.

In the ensuing discussion, when the team tried to understand the supervisor's request, the following sketches were produced:

The best tool for domain modeling is pen and paper or marker and index cards or whiteboard pens and whiteboards, because it focuses on the information to be exchanged rather than trying to make the sample or model "look beautiful". In other words, to prevent our messy handwriting from confusing you, we use graphical tools to create the model. So here's a cleaner version of the sample: