How do I need to change my app to adopt Swift Concurrency?

To adopt Swift Concurrency in your app, you need to follow several steps to ensure your code is concurrency-safe and takes full advantage of Swift's concurrency features. Here are some key points from the session "Migrate your app to Swift 6" at WWDC 2024:

Enable Swift 6 Language Mode: Start by enabling the Swift 6 language mode in your project settings. This will help protect against race conditions and ensure data isolation. You can do this by searching for "Swift Language Mode" in your project settings and setting it to Swift 6.
Adopt Concurrency Features: Use Swift's concurrency features such as async/await and actors to manage concurrent tasks. This helps in organizing your code and ensuring that operations are performed on the correct threads or actors.
Enable Complete Checking: Enable strict concurrency checking in your target's build settings. This will allow the compiler to check for possible race conditions and emit warnings for code that isn't concurrency-safe. Start with simpler targets like UI layers that often run on the main thread.
Handle Delegate Callbacks: When dealing with delegate callbacks, ensure you understand the concurrency guarantees provided by the framework. Annotate your protocols and delegates with @MainActor if they are expected to run on the main thread.
Gradual Migration: Migrate your code gradually, starting with enabling concurrency checking in simpler modules and then moving to more complex ones. This helps in identifying and resolving concurrency issues step by step.
Remove Unnecessary Annotations: With the latest SDKs, you might find that some @MainActor annotations are no longer necessary. Review and remove any redundant annotations to clean up your code.

For a detailed walkthrough, you can refer to the session Migrate your app to Swift 6 (08:53) which covers adopting concurrency features.

By following these steps, you can effectively migrate your app to use Swift Concurrency, improving its performance and safety.