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Derek Comartin

What are Business Rules? It’s not this.

What are business rules? Well, they often get confused with trivial validation. I think it’s essential to make the distinction because where you apply business rules and validation will differ and indicate the type of system you’re building. Let me explain and illustrate how you can make the distinction with a simple code example. YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Example Let’s immediately start with a very simple code example. Here’s a single method that has two conditions. The first is that if the… Read More »What are Business Rules? It’s not this.

Single() or First()? Understand the Abstractions you use!

Everything is built on layers of abstraction. But how well do you understand the abstractions of the tools, libraries, and frameworks you’re using? We know everything comes with trade-offs, and being informed about the underlying implementation can help you make better decisions. YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Example I posted a video, Refactoring code a better design, where I changed a call from First() to Single(). If you’re unfamiliar with LINQ or C#, First() is an extension on Enumerable<T> that returns you the… Read More »Single() or First()? Understand the Abstractions you use!

Code Review & Refactoring to a Better Design

It’s code review and design time. Recently, I recorded a video providing my thoughts on some code attempting to illustrate persistence ignorant for queries. I didn’t cover some specific API design decisions I disagreed with, around nullables and throwing exceptions. I’ll show samples of what I’d prefer the API to look like and why. YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Code Review This post reviews code that was initially in this code review post, “Clean Architecture” and indirection. No thanks. I that post/video was… Read More »Code Review & Refactoring to a Better Design