November 2025
Intermediate to advanced
464 pages
11h 25m
English
Content preview from Domain-Driven Transformation
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Part II. Technical, Tactical, and Team-Organizational Domain-Driven Transformation
Decomposing a legacy system with Domain-Driven Transformation is a major operation. Similar to a human before major surgery, you should make sure that the patient is in the best possible general health. How to do that is the topic of this second part of the book.
Most legacy systems we see are in poor general health—not only do they consist of one or more big ball(s) of mud, but they also suffer from the following problems:
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They have become rigid and inflexible and are difficult to change, and changes are very error prone due to the convoluted, difficult to understand structure.
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Overall, compared to systems with a good architecture, they have many undetected or even known errors, poor test coverage leading to the former, and many security gaps due to outdated libraries.
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They are difficult to build and deploy.
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They lack quality even at the level of simple code metrics, such as length of classes and methods, cycles between classes, number of parameters, etc.
If a legacy system is in such a distressed state, then we cannot immediately start with the strategic Domain-Driven Transformation (Part III). Rather, we must first improve the general condition of the legacy system to an appropriate level with appropriate measures that we describe in this second part of the book. In doing so, we will work on three levels to improve the general condition of our legacy system:
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Technical stabilization (see ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.