A few people have asked for online resources where I have learned about DDD and CQRS.

This post is a bit of a link dump.

The big one is the whole Tackling Business Complexity in a Microservice with DDD and CQRS Patterns section of this Microsoft e-book and the example Ordering Service in eShopOnContainers repository.

Then Herberto Graca’s DDD, Hexagonal, Onion, Clean, CQRS, … How I put it all together adds the Onion/Clean Architecture.

Some sample repositories that use this architecture are Jayson Taylor’s CleanArchitecture repo and TaskoMask.

For DDD base type implementations, Vladimir Khorikov’s entity implementation and a better Value Object implementration. In fact, I learned a lot from many of the posts on Vladimir Khorikov’s blog. You can also check out my own implementations too.

Regarding events and integration events, Kamil Grzybek’s Handling Domain Events: Missing Part and the post that it follows have been useful.

For higher-level domain architecture, I refer to Microsoft’s e-book again, Context Mapping and then a guide comparing a Shared Kernel, Conformist & Anti-Corruption Layer.

The following blog posts have ended up in my bookmarks too:

• A Brief Intro to Clean Architecture, Clean DDD, and CQRS
• Event-Sourcing as a DDD pattern
• CQRS: What? Why? How?
• Commands and Queries are Holistic Abstractions
• Read-models as a Tactical Pattern in Domain-Driven Design (DDD)
• Busting some CQRS myths
• Are You Making These 10 DDD Mistakes?