No More OOP - Functional DDD Without the Baggage

About the session

DDD tied itself to OOP only because OOP dominated the software world when DDD was born. That was never a deliberate design choice - just the perspective of people building business software on Java and .NET at the time. But let’s face it: OOP adds friction instead of clarity. In this talk, Oliver shows why it’s time to drop the OOP baggage and adopt a functional perspective on DDD: immutability, pure functions, and simple data structures.

We’ll challenge the myth that "anemic" models are a problem, showing instead how data objects plus pure functions form a clearer and more powerful foundation for domains. We’ll also explore how Event Sourcing thrives in this mindset, producing architectures that are expressive, resilient, and maintainable. With clear code and patterns, we’ll see how domains become easier to model, reason about, and evolve once we stop forcing OOP into DDD.