code design

Why Programmers Should Challenge the Stakeholders

Have you ever worked on a state of the art programming project? And then a new requirement arrives, it's implemented and suddenly you're working on a legacy project?

Guest post

My Code Design Training Reshaped

It is already more than one year and a half since I started to give my Code Design training. I have developed this training as I say here, out of the desire to teach others the way I link the learnings from the best practices books to the code I

Concurrent Unit Tests with Service Locator

My talk at Microsoft Summit created a nice discussion with some of the participants about writing isolated unit tests when using the Service Locator. It started from the part where I was showing how the AppBoot helps in dependencies management by enforcing consistency on how the Dependency Injection is done.

Speaker at Microsoft Summit

Last week I had the opportunity to speak for the first time at the Microsoft Summit. It was a nice and pleasant experience. I have talked about how we could achieve a high quality code design by enforcing consistency with the support of an Application Infrastructure in a large and

Crosscutting Concerns

The Crosscutting Concerns are the areas in which high-impact mistakes are most often made when designing an application. There are common causes that lead to this and there are common practices that can help to avoid such mistakes. In this post I will talk about the way I usually address

DRY vs Coupling

While reviewing my previous post another great discussion, which may arise from paying attention to your references, came to my mind: Don’t Repeat Yourself (DRY) vs Coupling. Each time you add a new reference it means that you want to call the code from the other assembly, therefore you

Using ReSharper for Assembly References Diagrams

A few posts back I talked about how we can use the assembly references to enforce consistency and separation of concerns (here and here are the old posts). I argue there that if we derive from the architecture the assemblies of our application, the kind of code (responsibility) each one

Localization Concern

Localization (also known as internationalization) is one of the concerns that is most of the times overlooked when we design an application. We almost never find it through the requirements, and if we do or if we ask about it, we usually postpone thinking about it and we underestimate the

Enforce Consistency with Assembly References

In this post I’ll describe some key aspects that I consider when designing the assemblies that build a system. When we structure our code into assemblies (generally named binaries, libraries or packages in other platforms than .NET) we are reasoning about three main things: * Deployment: different assemblies are deployed

Unit Testing on Top of Entity Framework DbContext

When writing unit tests one of the challenges is to isolate your tests from everything. To isolate them from the code that is not in their target and also from the other tests. As Roy Osherove puts it in his book “The Art of Unit Testing [...] a unit test should

Repository Implementations

In my previous post I have presented a way to separate your data access from the business logic, when a relational database is used. I have shown another implementation of the well-known Repository pattern. Since Martin Fowler described it in his book Patterns of Enterprise Application Architecture it became one

Separating Data Access Concern

In our days most of the applications that have a relational database as storage, use an ORM to access the data. The ORM (Entity Framework, Hibernate, etc.) does most of the data access implementation. Many of them have a modern API for querying data and for creating sessions of editing

Low Coupling by Refactoring Towards Higher Cohesion

Low coupling and high cohesion go hand in hand. In a low coupled design, the modules, classes and functions have a high cohesion. The other way around is also true: making high cohesive modules, classes or functions leads to a loosely coupled design. Why is this useful or interesting? The

Who Disposes Your Repository

Recently, I’ve went again through the discussion of how the Repository Pattern works with Dependency Injection (DI) in one of the projects I’m involved in. Even if these patterns are around for a while and there are many examples on how to use them together, discussing some particular