Get Your Hands Dirty on Clean Architecture

A good software architecture should keep the cost of development low over the complete lifetime of an application.

Ever wondered about how to actually implement a “Clean Architecture” or a “Hexagonal Architecture”? There’s a lot of noise around these keywords, but you can find very little hands-on material on this topic.

This book fills a void by providing a hands-on approach to the Hexagonal architecture style from the concepts behind it down to actual code.

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All About Hexagonal Architecture

• Learn the concepts behind “Clean Architecture” and “Hexagonal Architecture”.
• Explore a hands-on approach of implementing a Hexagonal architecture with example code on GitHub.
• Develop your domain code independent of database or web concerns.

Get a Grip on Your Layers

• Learn about potential problems of the common layered architecture style.
• Free your domain layer of oppressive dependencies using dependency inversion.
• Structure your code in an architecturally expressive way.
• Use different methods to enforce architectural boundaries.
• Learn the consequences of shortcuts and when to accept them.
• … and more.

What Readers Say

Tom Hombergs has done a terrific job in explaining clean architecture - from concepts to code. Really wish more technical books would be as clear as that one!

Gernot Starke - Fellow at INNOQ, Founder of arc42, Author of Software Architecture Books, Coach, and Consultant

Love your book. One of the most practical books on hexagonal architecture I have seen/read so far.

Marten Deinum - Spring Framework Contributor and Author of “Spring 5 Recipes” and “Spring Boot 2 Recipes”

A book taken right out of the machine room of software development. Tom talks straight from his experience and guides you through the day-to-day trade-offs necessary to deliver clean architecture.

Sebastian Kempken - Software Architect at Adcubum

Thank you for the great book, it helped me gain significant insight into how one would go about implementing hexagonal and DDD in a modern Spring project.

Spyros Vallianos - Java Developer at Konnekt-able

After reading it I had one of these ‘aha’ moments when things finally click in your brain.

Manos Tzagkarakis - Java Developer at Datawise

Table of Contents

1. What’s Wrong with Layers?
2. Inverting Dependencies
3. Organizing Code
4. Implementing a Use Case
5. Implementing a Web Adapter
6. Implementing a Persistence Adapter
7. Testing Architecture Elements
8. Mapping Between Boundaries
9. Assembling the Application
10. Enforcing Architecture Boundaries
11. Taking Shortcuts Consciously
12. Deciding on an Architecture Style

Questions? Comments?

Drop me an email.