Most software fails before a line of code is written. It fails when a product manager says "customer" and a developer hears a boolean flag in a database table. The words business and engineering use do not match, and each mismatch compounds into rework, defects, and a codebase nobody trusts. This book fixes that at the source by modeling complex software around the business it serves, with proven domain-driven design practices.

This practical field guide is for architects, senior developers, technical leads, product managers, and consultants who have watched business and engineering teams talk past each other. You will learn to build a ubiquitous language that survives the jump from conversation to code, draw bounded contexts aligned with how teams work, design aggregates that protect business invariants, distinguish entities from value objects, and model domain events in the past tense. You will also learn when DDD is the wrong tool, how to win organizational buy-in, and how AI assistants accelerate discovery and validation. Inside you will find:

• A real insurance case where the term policy effective date hid 4 distinct meanings and caused years of bugs • Core, supporting, and generic subdomains, and where to invest your modeling effort • The context map and relationship patterns, from anticorruption layers to shared kernels • Aggregate design heuristics based on invariants, not data access patterns • Event storming workshops that turn sticky notes into bounded contexts and domain events • Translating the model into code with repositories, application services, and Gherkin acceptance tests

Modeling done well does not add complexity, it removes the accidental complexity of translation. Teams that invest in a shared language ship faster, fix fewer bugs, and onboard new developers in days instead of weeks. Start with one bounded context, define its terms, encode them in code and tests, and let the improvements compound. You do not need every pattern at once.

© 2026 BGB Learn (E-Book): 6610001334802

Erscheinungsdatum

E-Book: 18. August 2026