A DSL, short for Domain Specific Language, can be explained as a special kind of API that focuses on providing a simple syntax that's tailored to working within a specific domain.

While DSLs are often written in more dynamic languages, such as Ruby - Swift's type inference and overloading capabilities also make it a really great language to build DSLs in - and this week, let's do just that!

Most modern apps require some form of networking - which means working with URLs in different shapes and forms. However, constructing URLs - especially dynamic ones based on user input - isn't always straight forward, and can lead to a wide range of bugs and problems if we're not careful.

This week, let's take a look at various techniques for working with URLs in Swift, how to make our URL construction code more robust, and how different kinds of URLs might warrant different approaches.

The way that an app’s data is used tends to vary quite a lot depending on what view the data is being displayed in - requiring custom data logic for each view.

View models attempt to make it easier to write and maintain such logic, by introducing dedicated types for it. This week, let’s take a look at a few different ways that various flavors of view models can be implemented in Swift.

Asynchronous code is essential to providing a good user experience, but can at times be really tricky to write, debug and especially test.

This week - let's explore how we can make our asynchronous tests much simpler, inspired by the async/await programming paradigm.

Lists and collections of items are arguably two of the most common types of UIs found in apps - rendered through a UITableView or a UICollectionView.

This week, let's take a look at how we can implement data sources for table- and collection views in a more reusable manner, and how doing so can let us make our list-based UI code more composable and easier to work with.

Separation of concerns is one of the most universally recognized programming principles - but in practice, it can be easier said than done, especially when it comes to UI development.

This week, let’s take a look at how we can use the presenter pattern to move some code normally contained within view controllers - specifically related to the presentation of additional UIs - into separate, dedicated types, to improve our separation of concerns.

This week, let's take a look at how we can be inspired by the functional programming world to improve the structure and robustness of our Swift code - this time focusing on using functions that return objects and values as early as possible.

With each new release, Swift keeps getting better and better at creating compiler-generated implementations of common boilerplate. One such new feature in Swift 4.2 is the new CaseIterable protocol - that enables us to tell the compiler to automatically synthesize an allCases collection for any RawRepresentable enum. This week, let's take a look at some examples of scenarios in which this new feature can come very much in handy.

Proper encapsulation of logic is one of the most important things when it comes to building well-architected apps and systems. By limiting access to a given value or object to those that really need it, we can create more well-defined relationships and reduce the amount of code paths that we need to test. This week - let's take a look at how we can improve encapsulation in our model layer, using model controllers.

Adding new features to an app or framework often involves adding new arguments to existing functions. While most such changes may seem trivial at first, if we're not careful, we could - over time - end up with functions that are a bit unclear and cumbersome to use. This week, let's take a look at how to deal with such functions, and how they often can be simplified by reducing the number of arguments they accept.

Type inference is a key feature of the Swift type system and plays a big part in the syntax of the language - making it less verbose by eliminating the need for manual type annotations where the compiler itself can infer the types of various values.

This week, let's take a look at how we can make Swift's Codable API a bit nicer and less verbose to use, by leveraging the power of type inference.

One thing that almost all apps and frameworks have in common is that they tend to grow in both size and complexity as time passes. As a project grows it becomes more and more important to maintain a solid and consistent structure, but at the same time it also becomes increasingly difficult to do so.

This week, let's take a look at some tips and tricks as to how we can improve the structure of our Swift projects in a few key ways.

Adding new features to existing code can be really challenging - especially if that code is heavily used throughout one or many projects. Backward compatibility can in many ways help us make such changes in a much smoother fashion, so this week, let's take a look at a few different techniques that can help us make changes to our code base fully backward compatible.

Unit testing can be a great tool in order to improve the quality of an app, and to enable the team working on it to iterate and release faster and more often. However, being able to use unit testing in a productive way also requires the various parts of an app to be written with testability in mind, which isn't always the case.

This week, let's take a look at a few different refactoring techniques that can help us make non-testable code much easier to test.

While subclassing is not universally bad, avoiding it can in many situations leave us with simpler code that is easier to change and reuse. This week, let's take a look at a few different techniques that can help us write subclass-free view controllers, and how it can help us avoid the Massive View Controller problem.

View controller containment has been an essential part of UIKit ever since the early days of the iPhone. This week, let's take a look at how we can build our own container view controllers, and how doing so can help us make parts of our UI code more modular and easier to manage.

One of the most important aspects of any app's architecture is how data and models are dealt with. Building a robust model structure and establishing well-defined data flows can really help us avoid a large set of bugs and problems, but at the same time we also need to make our model code easy to use and maintain.

This week, let's take a look at a few different techniques that can help us make code dealing with mutable models a bit more predictable.

When writing tests for any application, it's always important to consider what the debugging experience will be like when they eventually start failing. After all, the purpose of all kinds of automated tests is to eventually fail - since it'll let us catch bugs and errors before they reach our users.

This week, let's take a look at a few different scenarios, and how we - with just a few subtle tweaks - can make our tests a lot easier to debug.

Most objects require some form of setup before they're ready to be used in an app. While it’s very common to create subclasses for that purpose, this week, let's take a look at an alternative approach to writing setup code that doesn't require any form of subclassing - by using static factory methods.