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Modern Swift Lock: Mutex & the Synchronization Framework
Swift offers several solutions to lock access to mutable content and prevent so-called data races. Locks like NSLock, DispatchSemaphore, or ...
Swift Concurrency & Swift 6 Course (Launch offer)
A Swift Concurrency Course that helps you learn all the fundamentals of Swift Concurrency and migrate your projects smoothly to ...
Sparkle: Distribution apps in- and out of the Mac App Store
By implementing Sparkle into RocketSim, I've been able to allow developers to install my app on macOS outside of the ...
Transform Your Career with the iOS Lead Essentials — Limited Offer
Unlock over 40 hours of expert training, mentorship, and community support to secure your place among the best devs. Click now for early access to this limited offer and a FREE crash course!
The Essential Swift Concurrency Course for a Seamless Swift 6 Migration.
Learn all about Swift Concurrency in my flagship course offering 58+ lessons, videos, code examples, and an official certificate of completion.
Updated for Swift 6.2 and now available with a limited-time launch offer.
Swift Keywords
Do you know how to use each keyword in Swift?
Click on the keyword to learn more and explore code examples.
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Learn more about Swift
Swift Concurrency & Swift 6 Course (Launch offer)
A Swift Concurrency Course that helps you learn all the fundamentals of Swift Concurrency and migrate your projects smoothly to ...
#Playground Macro: Running Code Snippets in Xcode’s canvas
Xcode 26 introduced a new #Playground macro that allows you to run code snippets and preview them in Xcode's canvas ...
@concurrent explained with code examples
Swift 6.2 introduced many changes during WWDC 2025, including a new @concurrent attribute we need when working with Swift Concurrency ...
Learn SwiftUI
Universal Links implementation on iOS
Universal Links allow you to link to content inside your app when a user opens a particular URL. Webpages will ...
SwiftUI ForEach Explained with Code Examples
If you're building dynamic lists or repeating UI components in SwiftUI, there's a high chance you're already using the SwiftUI ...
SwiftUI Alert Guide + Code Examples
You can present a SwiftUI Alert using dedicated view modifiers that make it straightforward to present native alerts. It works ...
Build Apps Faster using RocketSim
Recommend by Apple as an “Essential Tool for Developers”, RocketSim helps thousands of engineers to save hours per week. Discover these articles and learn how you can leverage RocketSim to improve your workflow:
App Actions
- Inspect network traffic using the Xcode Simulator
- Universal Links implementation on iOS
- Deeplink URL handling in SwiftUI
- Location Simulation in Xcode’s Simulator
- Optimizing your app for Network Reachability
- Testing push notifications on the iOS simulator
App Actions Perform Menu
- Localization testing in Xcode
- User Defaults reading and writing in Swift
- Xcode Simulator Directories Exploration
RocketSim Tools
Combine all the things
@Published risks and usage explained with code examples
@Published is one of the property wrappers in SwiftUI that allows us to trigger a view redraw whenever changes occur ...
RunLoop.main vs DispatchQueue.main: The differences explained
RunLoop.main and DispatchQueue.main are often used as schedulers within Combine. During code reviews, I often encounter inconsistency in using one ...
PassthroughSubject vs. CurrentValueSubject explained
PassthroughSubject and CurrentValueSubject are two types from the Combine framework that conforms to the Subject protocol. Both are very similar ...
Transform Your Career with the iOS Lead Essentials — Limited Offer
Unlock over 40 hours of expert training, mentorship, and community support to secure your place among the best devs. Click now for early access to this limited offer and a FREE crash course!
Dive into Core Data
How to observe NSManagedObject changes in Core Data using Combine
Observing changes in Core Data NSManagedObject instances with Combine publishers can be a great solution to keep your user interface ...
Data validation on insertion, update, and deletion in Core Data
Data validation in apps is important to make sure we save data conforming to the business rules. A name should ...
Derived Attributes to improve Core Data Fetch Performance
Derived attributes are available since iOS 13 and aim to improve fetch performance in many different scenarios. Although we have ...
Be an expert on Xcode
Sparkle: Distribution apps in- and out of the Mac App Store
By implementing Sparkle into RocketSim, I've been able to allow developers to install my app on macOS outside of the ...
RocketSim 13.0: Builds Apps Faster
RocketSim is a developer tool that gives your Xcode Simulator extra functionalities to increase day-to-day development productivity. A floating window ...
Inspect network traffic using the Xcode Simulator
Inspecting network traffic is an essential skill for app developers. Several tools allow you to monitor requests going in and ...
Get better at debugging
Network Link Conditioner: Simulating Slow Networking
The Network Link Conditioner allows you to test your apps under slow networking conditions on macOS and iOS. The tool ...
Memory consumption when loading UIImage from disk
Memory consumption can quickly increase if you load many images from the disk using UIImage. You'll generally load images from ...
Debugging SwiftUI views: what caused that change?
Debugging SwiftUI views is an essential skill when writing dynamic views with several redrawing triggers. Property wrappers like @State and ...
Improve your workflow
Testing push notifications on the iOS simulator
Testing push notifications in the iOS simulator makes adding support for remote notifications much more effortless. However, you often must ...
Designing Apps: 5 Methods to improve your workflow
Designing apps can be challenging if you don't have a design background. Many of you who read my blog are ...
Test-Driven Development (TDD) for bug fixes in Swift
Test-driven development (TDD) is a technique that requires you first to write a failing test before you start implementing a ...
Optimize yourself and improve
Billing Grace Period Explained: How It Works and Why It Matters
Users with auto-renewable subscriptions can enter a billing grace period if their automatic payment failed. In this period, they can ...
Institutional Purchases: Understanding and Detecting
A download spike caused by Institutional purchases visible in App Store Connect causes confusion to many app developers. Several posts ...
Network Link Conditioner: Simulating Slow Networking
The Network Link Conditioner allows you to test your apps under slow networking conditions on macOS and iOS. The tool ...
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Most Popular Posts
- Modern Swift Lock: Mutex & the Synchronization Framework
- Async await in Swift explained with code examples
- Sendable and @Sendable closures explained with code examples
- MainActor usage in Swift explained to dispatch to the main thread
- SwiftUI TabView: Explained with Code Examples