I'll be writing a book about Hexagonal Architecture

If you have questions about Hexagonal Architecture, if you see gaps between HA and your real-life projects, then I'd like to hear from you. See the Discord link at the bottom of this post.

Hexagonal Architecture meets real-life projects. And then developers start asking themselves these questions:

1. Hexagonal Architecture tells us to abstract away databases - with repository interfaces. But ORMs do this already. Should we, or should we not, create our own repository interfaces?

2. How should we represent use cases? Application Services or Command Handlers? Coarse-grained or granular? Should we have interfaces for Driver Ports or no interfaces for Driver Ports?

3. Hexagonal Architecture does not prescribe the structure inside the Hexagon. So what are the options we have for structuring inside the Hexagon? Must we use DDD inside the Hexagon or not?

4. What happens when business logic is not just in the application? What happens when business logic is in the database (e.g., performance reasons)? What about the read side?

5. Why are Test Adapters only targeting the Application? Should the Adapters not be tested (they’re just glue), or should they be tested, and how?

I am planning to write a book about HA

Why I’m writing a book about HA?

• I’ve done several meetups about Hexagonal Architecture, saw high interest from the audience and lots of interesting questions (for example - you encounter a challenge in an actual life project, and it’s not clear how to do it the HA way)

• I’ve already written many articles about Hexagonal Architecture - though I realized it would take hours for someone to read it all, and readers showed interest in presenting it in a more structured step-by-step way.

• People have many real-life questions where the solution isn’t present in the raw theory of HA - so it would use helpful to present both the raw theory and the alternative practical implementations with pros and cons.

So I plan to write a book about Hexagonal Architecture to condense the material in a structured easy-to-digest way (so that you don't have to read through hundreds of my posts and meetups) and also to have code samples to illustrate.

What do you want to know about HA?

1. What questions do you have about Hexagonal Architecture?

2. What is the gap between the theory and your real-life work?

3. What would you like me to address in my book?

I’d like to hear about your team’s tech stack and whether you use monoliths or microservices. Furthermore, as you’ve been reading my articles and watching YouTube videos, what questions do you have about Hexagonal Architecture in your real-life work? Which questions I hadn’t addressed and should I address further?

Your questions about HA are very important to me because I am using this as “input” for writing the book (i.e., to address your questions), so what you say matters to me a lot. The book's intention is not yet another theoretical overview but guidance you can use in real projects.

What do you want to be in the book?

I’d like to hear from you - what questions you’d like me to address about Hexagonal Architecture, and if you tried implementing it in real-life projects, what questions do you have about it?

You can write to me on my Optivem Discord community (in the #books channel): you can join here: https://discord.gg/ref9xMJzHX

Please post your feedback during July & early-mid August so that I can consider it as I write the book. If I receive your feedback later, I may be unable to process it.