• DDD Weekly: Issue #21 - Using CQRS with Event Sourcing [blog] Kristian Freed. “…enter CQRS – Command Query Responsibility Segregation. CQRS, in contrast with CRUD, starts with the observation that reading and writing data are very different things.” Going “Events-First” for Microservices with Event Storming and DDD [blog] Russ Miles. “Events turn out to better capture the ubiquitous language of a domain or system. More often than not the easiest way to describe the system is in terms of the things that happen, not the things that do the work when collaborating with non-technical stakeholders” [DDD Weekly]
• OCP vs YAGNI - In this post, I want to cover the topic of OCP vs YAGNI - contradictions between the Open/Closed Principle and the You aren’t gonna need it one. OCP Let’s start with a refresher for what OCP is. The Open/Closed principle states that: Software entities (classes, modules, functions, etc.) should be open for extension, but closed for modification. It was first introduced by Bertrand Meyer in his canonical Object-Oriented Software Construction book. [Enterprise Craftsmanship]

Permalink | From 28 November 2016 to 04 December 2016 | Last updated on: Mon, 7 Jun 2021 09:11:14 GMT

• DDD Weekly: Issue #20 - Event sourcing at global scale [blog] Martin Krasser. “Together with an international customer, I recently started to explore several options how to globally distribute an application that is based on event sourcing.” Value Object [blog] Martin Fowler. “I find that value objects, particularly small ones, are often overlooked - seen as too trivial to be worth thinking about. But once I’ve spotted a good set of value objects, I find I can create a rich behavior over them. [DDD Weekly]
• When to include external systems in testing scope - Should you always mock out your database? Or should you include it in the unit/integration testing scope? What about other external systems? This post is based on my Pluralsight course about Pragmatic Unit Testing. Two types of external dependencies When it comes to external dependencies (dependencies outside the process that hosts your application, such as a database, a 3rd party system, etc.), there’s no single guideline regarding how to work with them in tests. [Enterprise Craftsmanship]

Permalink | From 14 November 2016 to 20 November 2016 | Last updated on: Mon, 7 Jun 2021 09:11:14 GMT

• DDD Weekly: Issue #19 - Reactive DDD with Akka - Reactive business processes [blog] Pawel Kaczor. “Once we start modeling the interactions that shape our business domain, using the language of the commands and the events, we are on a good way towards creating a model of a system that is simple to understand by the business people and also simple to express in the code.” A Brief History of Distributed Programming: RPC [video] Christopher Meiklejohn. [DDD Weekly]
• On Being Explicit - Video of my talk at Agile Testing & BDD eXchange 2016 in LondonVideo of my talk at the DDD London meetup Slides: Abstract “Make the implicit explicit” must be one of the most valuable advices I ever got about software modelling and design. Gather around for some tales from the trenches: stories from software projects where identifying a missing concept, and bringing it front and centre, turned the model inside out. Our tools: metaphors, pedantry, type systems, the age old heuristic of “Follow the money”, visual models, and a healthy obsession with language. [Mathias Verraes]

Permalink | From 07 November 2016 to 13 November 2016 | Last updated on: Mon, 7 Jun 2021 09:11:25 GMT