A recent paradigm shift I have been trying to make is to using messaging patterns in my project. One impact of this shift has been a more granular approach to various commands against the domain which somehow changes its state. While I do my best to stick to DDD (Domain Driven Design) modeling patterns and concepts I confess I slide into a CRUD based approach to various actions in the system - lots of data in, lots of data out. This is partly due to the nature of the requirements and partly due to lack of creative thinking regarding what business rules should be enforced on the domain. As I started to examine where my weak points were in my application I realized I was doing an awful lot of mapping between view objects and domain entities within the Application Service layer which was being called by my Controllers in the web app. This is fine for simple cases but collections of value objects or cross-aggregate references can soon result in too much conditional or procedural code. Then I came across this post by Udi Dahan about getting away from CRUD mentality into a more DDD approach. I had read this before but I didn't "get" it so much. Particularly revealing to me was in the comments where Udi explains a method which...