To build software, we use great technologies, programming languages, and tools. And we have a lot of fun programming in this technical environment. But we must not forget that the most important point for a successful project is not the technology but the *domain*! To understand the domain we need a common language with the domain experts. Also, if we don't reflect the domain model in the software and its architecture, it will not help our users doing their work.

It is easy for developers to fall into the trap of focussing on technology instead of the domain. To prevent you from this, I will show in this talk how Domain-Driven Design (DDD) can help you to gather the domain knowledge and transform it into a Ubiquitous Language. To do this we use techniques like Interviews, Domain Storytelling, and Event Storming.

In practice it is not easy to decide how to divide up the domain and develop microservices for it. Here the DDD pattern Bounded Context can help us. It shows us where vertical cuts can be made.

Using these tools together with the Building Blocks of DDD enables us to build an architecture that represents the domain and makes our users happy.