Hi, my name is Donny
I'm a curious, passionate iOS Developer from The Netherlands who loves learning and sharing knowledge.
Take a look at my books
Practical Swift Concurrency
Learn everything you need to know to make optimal use of Swift Concurrency in your applications. This book covers everything from awaiting asynchronous method calls to building your own highly concurrent systems. It’s a great introduction for those looking to familiarize themselves with everything Swift Concurrency has to offer.
Buy on GumroadPractical Combine
Practical Combine is a book aimed at intermediate to advanced developers who want to learn more about Apple's Combine framework. This book takes you all the way from the basics to building custom Combine publishers using Practical, useful examples that you can start using immediately.
Buy on GumroadPractical Core Data
Practical Core Data is for intermediate to advanced developers who want to learn more about Core Data. Whether you're new to Core Data, or tried using it years ago, you'll find that Practical Core Data introduces you to all the essentials to get you up and running with the framework.
Buy on GumroadRecent articles
Jump to a random postImproving test coverage with parameterized tests in Swift testing
October 31, 2024When you subscribe to the practice of test-driven development or just writing tests in general you'll typically find that you're going to be writing lots and lots of tests for pretty much everything in your codebase. This includes testing that varying inputs on the same function or on the same object result in expected behavior. For example, if you have a function that takes user input and you want to make sure that you validate that a user has not...
Read more...Swift Testing basics explained
October 23, 2024Swift testing is Apple's framework for running unit tests in a modern and more elegant way than it was with XCTest, which came before it. This post is the first one in a series of posts that will help you start using Swift Testing in your projects. In this post, we'll take a look at the following topics: Adding a Swift Testing to an existing project Writing your first Swift test Understanding Swift Testing syntax Let's go ahead and dive...
Read more...Testing completion handler APIs with Swift Testing
October 16, 2024The Swift testing framework is an incredibly useful tool that allows us to write more expressive tests with convenient and modern APIs. This is my first post about Swift Testing, and I’m mainly writing it because I wanted to write about something that I encountered not too long ago when I tried to use Swift testing on a code base where I had both async code as well as older completion handler based code. The async code was very easy...
Read more...What is dependency injection in Swift?
October 11, 2024Code has dependencies. It’s something that I consider universally true in one way or another. Sometimes these dependencies are third party dependencies while other times you’ll have objects that depend on other objects or functionality to function. Even when you write a function that should be called with a simple input like a number, that’s a dependency. We often don’t really consider the small things the be dependencies and this post will not focus on that at all. In an...
Read more...Getting started with Mesh Gradients on iOS 18
September 25, 2024With iOS 18, we have the possibility to create mesh gradients. Mesh gradients are a really nice way to create very cool UI effects. In this post, we're going to explore exactly what mesh gradients are, how we can use them, and how we can even animate them to look really cool. We’ll start off looking at how we can create a mesh gradient. We're going to take a look at how it more or less works, and then we'll...
Read more...Animating SF Symbols on iOS 18
September 4, 2024Over the years, Apple has been putting tons of work into the SF Symbols catalog. With SF Symbols, we’re able to leverage built-in iconography that will look familiar to users while also fitting into the Apple ecosystem very nicely. The fact that there’s thousands of symbols to choose from makes it a highly flexible and powerful catalog of icons that, in my opinion, should be every designer and developer’s first choice when they’re looking for visual components to add to...
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