WWDC25: Code-along: Elevate an app with Swift concurrency | Apple

Video Description

Learn how to optimize your app’s user experience with Swift concurrency as we update an existing sample app. We’ll start with a main-actor app, then gradually introduce asynchronous code as we need to. We’ll use tasks to optimize code running on the main actor, and discover how to parallelize code by offloading work to the background. We’ll explore what data-race safety provides, and work through interpreting and fixing data-race safety errors. Finally, we’ll show how you can make the most out of structured concurrency in the context of an app. Explore related documentation, sample code, and more: Swift Migration Guide: https://www.swift.org/migration/documentation/migrationguide/ Code-along: Elevating an app with Swift concurrency: https://developer.apple.com/documentation/Swift/code-along-elevating-an-app-with-swift-concurrency Embracing Swift concurrency: https://developer.apple.com/videos/play/wwdc2025/268 Analyze hangs with Instruments: https://developer.apple.com/videos/play/wwdc2023/10248 Explore concurrency in SwiftUI: https://developer.apple.com/videos/play/wwdc2025/266 Beyond the basics of structured concurrency: https://developer.apple.com/videos/play/wwdc2023/10170 00:00 - Introduction 02:11 - Approachable concurrency configuration 02:51 - Sample app architecture 03:42 - Asynchronously loading photos from the photo library 09:03 - Extracting the sticker and the colors from the photo 12:30 - Running tasks on a background thread 15:58 - Parallelizing tasks 18:44 - Preventing data races with Swift 6 27:56 - Controlling asynchronous code with structured concurrency 31:36 - Wrap-up More Apple Developer resources: Video sessions: https://apple.co/VideoSessions Documentation: https://apple.co/DeveloperDocs Forums: https://apple.co/DeveloperForums App: https://apple.co/DeveloperApp