During a recent run of my Advanced Web Application Architecture training, we discussed the distinction between infrastructure code and non-infrastructure code, which I usually call core code. One of the participants summarized the difference between the two as: "everything in your vendor directory is infrastructure code". I don't agree with that, and I will explain why in this article.

Here are some rules I use for working with dynamic arrays. It's pretty much a Style Guide for Array Design, but it didn't feel right to add it to the Object Design Style Guide, because not every object-oriented language has dynamic arrays. The examples in this post are written in PHP, because PHP is pretty much Java (which might be familiar), but with dynamic arrays instead of built-in collection classes and interfaces.

Today Manning released my latest book! It's called "Object Design Style Guide".

In November 2018 I started working on this book. The idea for it came from a conversation I had with the friendly folks at Akeneo (Nantes) earlier that year. It turned out that, after days of high level training on web application architecture and Domain-Driven Design, there was a need for some kind of manual for low level object-oriented programming. Not as low level as the kind of programming advice people usually refer to as clean code, but general programming rules for different kinds of objects. For instance:

• A service gets its dependencies and configuration values injected as constructor arguments.
• A service is an immutable object.
• An entity always has a named constructor.
• An entity is the only type of mutable object in an application.

And so on...