Domain-Driven Design Distilled

I kind of always had this hunch that Domain-Driven Design was something of a buzzword fad, that it likely described something I was already doing regularly and that the book and the approach likely just lent formality and terminology to common sense activities. After all, the biggest thing I see referenced seems to be this Ubiquitous Language stuff, which I think just means using the same nouns for stuff as the domain experts, which I try to do anyway so I'm sure I'm already doing everything in the book, right? Nope. I was flat wrong, which is why I consider this book a must-read for engineers who do a lot of greenfield work, domain modeling, and architecture.

Early on, the author provides a sort of toy example that will stay with us for the duration of the book, designing the domain for a Scrum management product. I've actually worked a job where I did this very thing, so this resonated fairly strongly. The book suggests that, if engineers are left to their own devices, they'll design around code generality to reduce duplication, so there might be like a ScrumElement that could be a Product or a BacklogItem, and there's like a generic ScrumElementContainer which could be either a Sprint or Release. I'm just reading this section like, yeah, that's exactly what I would do... in fact I did that. Is that bad? But the rest of the book explains exactly why that's bad, and exactly how to do it better. Chapter after chapter, the book showed me the ways in which my approach to domain modeling was disastrously bad and how much better it could be. It also explained how, with this alternative approach, my domain would lend itself more easily to modular system design along service-oriented boundaries.

In short, this book is excellent and completely changed how I think about and model domain objects at work. The book can sometimes be light on detail, I often found myself wanting more information, or stronger examples of exactly how something should work, but at the end of the day that's the purpose of this book - a short introduction that encourages the reader to dive in deeper with Domain Driven Design or Implementing Domain Driven Design. As such, I can't really complain about the general lightness of this book, as it's the primary reason it was such an easily digestible 197 pages.

Overall, this book is a must-read, I wish it existed years ago. I think back to all the times that a group of coworkers and I would gather in front of a whiteboard and model domain objects together without a single domain expert in the room. It makes me slap my head at how idiotic my approach has been for over a decade, the ways that I let database and technical concerns dictate the design of domain objects rather than the business's needs. I can never look at this regularly-performed process the same way, which is why it joins my list of Career-Changing Books.