Weekly Swift articles, podcasts and tips by John Sundell.
Swift by Sundell is updated every single week, all year round. This page contains the latest updates.
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On this special episode, John is joined by the entire team behind the award-winning apps Halide and Spectre, Apple’s 2019 App of the Year. Ben, Sebastiaan and Rebecca share their stories of how these apps came to life, how they’re working together between design and development, and how technologies like Computational Photography and Augmented Reality are influencing their work.
A summary of all Swift by Sundell content published during May 2020.
This week’s article is about library development, and contains a few techniques and principles that can be good to keep in mind when designing and building reusable Swift libraries.
How I got started with programming, writing, and podcasting.
Testable code without any protocols.
Let’s take a look at a number of techniques, patterns, and ways of structuring UI code that can help us get the very most out of Xcode’s SwiftUI-powered preview system.
In this Basics article, let’s take a look at a few examples of the various kinds of properties that Swift supports, and what their characteristics are.
In this article, I’ll aim to explain both why I chose not to use any client-side JavaScript when building Swift by Sundell, and why I thought that it was important to emphasize that fact at the bottom of every page.
Kyle Lee, also known as Kilo Loco, joins John to go behind the scenes of Publish — the static site generator used to build Swift by Sundell. Also, how to make a code base accessible to new team members, learning from open source, getting started with Swift-based web development, and much more.
This week, let’s take a look at a few techniques that can help us make our code easier to read, test and maintain, by reducing the amount of indentation within it.
Making it easy to observe a single value in a read-only fashion.
Adding more contextual information to test failures.
Let’s take a look at a few techniques that can make it much simpler to propagate runtime errors to our users, and how employing some of those techniques could help us present richer error messages without having to add a ton of complexity within each UI implementation.
Let’s take a look at how Swift’s key paths work, and how they relate to functions — both in terms of what comes built into the language itself, and what kind of utilities that we can write ourselves to form some really nice convenience APIs.
Tobias Due Munk joins John to talk about using SwiftUI to build prototypes, how third party developers can extend SwiftUI’s built-in APIs in various ways, and to discuss the challenges of writing highly dynamic systems in Swift.
Celebrating this website’s three-year anniversary.
My latest guest post on the Bitrise blog contains my top UI testing tips.
Swift’s many protocols can, in general, be split up into four main categories. Let’s go through them, and how keeping them in mind can help us write well-formed protocols that are consistent with those found in the standard library.
Sometimes, we’re able to omit certain generic type constraints.
A summary of all Swift by Sundell content published during April 2020.
Let’s take a look at the role that controllers play within the MVC design pattern, and how we can avoid some of the most common issues when working with them — particularly around how we can break up Massive View Controllers into smaller building blocks.
This week, let’s explore how we can make use of the standard library’s built-in algorithms when performing various types of queries against collections of values.
Dave Abrahams joins John to talk about Protocol-Oriented Programming and how to make the most out of the Swift Standard Library. Also, discussions on Swift’s overall design, why it puts such a strong emphasis on value types and protocols, and how it’s been influenced by other languages.
Defining Swift enums based on completely custom types.
Swift enums are really powerful, but they can often be made even more capable when mixed with other kinds of Swift types — such as protocols and structs. This week, let’s take a look at a few examples of doing just that.