Learning Domain-Driven Design

Chapter 13. Domain-Driven Design in the Real World

We have covered domain-driven design tools for analyzing business domains, sharing knowledge, and making strategic and tactical design decisions. Just imagine how fun it will be to apply this knowledge in practice. Let’s consider a scenario in which you are working on a greenfield project. All of your coworkers have a strong grasp of domain-driven design, and right from the get-go all are doing their best to design effective models and, of course, are devotedly using the ubiquitous language. As the project advances, the bounded contexts’ boundaries are explicit and effective in protecting the business domain models. Finally, since all tactical design decisions are aligned with the business strategy, the codebase is always in great shape: it speaks the ubiquitous language and implements the design patterns that accommodate the model’s complexity. Now wake up.

Your chances of experiencing the laboratory conditions I just described are about as good as winning the lottery. Of course, it’s possible, but not likely. Unfortunately, many people mistakenly believe that domain-driven design can only be applied in greenfield projects and in ideal conditions in which everybody on the team is a DDD black belt. Ironically, the projects that can benefit from DDD the most are the brownfield projects: those that already proved their business viability and need a shake-up to fight accumulated technical debt and design entropy. Coincidentally, ...