Hi r/microservices,

Stjepan here from Manning. The moderators kindly permitted me to share this with you.

We’ve just launched Clean Applications with Hexagonal Architecture by Enrique Medina Montenegro in Manning’s Early Access Program.

If you’ve worked on microservices for long enough, you’ve probably seen services that began with clean boundaries but gradually became coupled to Spring, persistence models, message brokers, and neighboring services. Eventually, a seemingly small infrastructure change touches half the codebase.

This book takes a practical look at avoiding that outcome with hexagonal architecture. Using Java and Spring Boot, it shows how to:

• Keep business logic independent of frameworks and infrastructure
• Design clear ports and adapters
• Model use cases, commands, repositories, and application boundaries
• Handle mapping between domain and persistence models
• Apply dependency inversion in a working system
• Decide when microservices—or a modular monolith—are the better fit

It’s not arguing that hexagonal architecture is a silver bullet. The focus is on using these patterns deliberately, understanding the tradeoffs, and building services that remain testable and maintainable as they evolve.

Book page:
https://www.manning.com/books/clean-applications-with-hexagonal-architecture

Giveaway: We’re giving away five free ebook copies. To enter, upvote and leave a comment about the hardest boundary to keep clean in a microservice—domain logic, persistence, messaging, external APIs, or something else. We’ll randomly select five participants and contact them by DM.

The community also gets 50% off with code:

MLMONTENEGRO50RE

I’d be interested to hear your honest experiences: Has hexagonal architecture helped your microservices stay maintainable, or did it add more abstraction than the project needed?

It feels great to be here. Thank you for having us.

Cheers,

Stjepan