juniorDDD

What is Domain-Driven Design (DDD)?

Updated Apr 28, 2026

Short answer

DDD is an approach to software development that focuses on complex domains by connecting the implementation to an evolving model of core business concepts.

Deep explanation

DDD is not just about coding; it's about modeling the business. By using Ubiquitous Language, we ensure the code reflects the mental model of the domain experts. Entities handle identity (like a User ID), while Value Objects handle data (like an Address).

Real-world example

An e-commerce system where 'Order' is an Entity, but 'Shipping Address' is a Value Object.

Common mistakes

  • Making everything an Entity even if it doesn't need identity.

Follow-up questions

  • Why are Value Objects immutable?

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