What is Swift concurrency? A friendly guide an 8-year-old could follow: async/await, tasks, actors, the MainActor, Sendable and the runtime every iOS app runs on.

The sending keyword lets a non-Sendable value cross into an actor safely in Swift 6. See what the compiler accepts and rejects, tested on Swift 6.2 and 6.4.

Debounce search in SwiftUI with .task(id:) and Task.sleep: one request after typing stops and no stale results. Tested on Swift 6.2 and 6.4.

AI tools and new hires both copy the patterns they find. Why a shared, predictable iOS layout like CFA helps them, and why Frankenstein Architecture confuses them.

Yes: async throws(E) works in Swift 6. See where typed throws keeps its error type, where it widens to any Error, tested on Swift 6.2 and 6.4.

Use withDiscardingTaskGroup when child tasks only cause effects. A discarding task group explained with SE-0381, tested memory numbers and error behaviour in Swift concurrency.

Yes. Since SE-0310 a read-only computed property can be async or throws. See get async in protocols, actor snapshots and the exact compiler errors, tested on Swift 6.2.

What does an isolated parameter do in Swift? How isolated (any Actor)? = #isolation keeps a helper on its caller's actor, tested on Swift 6.2 and 6.4.

How do you observe an @Observable model with async/await? Swift Observations (SE-0475), tested on Swift 6.2 and 6.4: first values, transactions, skipped values and ending the loop.

Do you need [weak self] in a Swift Task? Tested on Swift 6.2 and 6.4: when strong self is fine, when a task causes a retain cycle and memory leak, and two fixes.

Swift async map explained: why map rejects await, a sequential asyncMap, and a task group concurrentMap that preserves order and limits concurrency.

Fix 'actor-isolated cannot satisfy nonisolated requirement': async protocol requirements, nonisolated Hashable and Identifiable, and protocols that refine Actor.

Why a @MainActor class's deinit isn't isolated, what Swift 6.2's isolated deinit changes, when the cleanup runs, and the rules the compiler enforces, with tested code.

Retry async/await calls in Swift without hammering a server: exponential backoff with jitter, which errors to retry, and cancellation, with tested results.

Two loops on one AsyncStream split its values. Learn the queue-not-radio model, build a per-subscriber broadcaster, and compare it with AsyncAlgorithms share().

Add a timeout to async code in Swift with a task group race, see why cancellation decides when it returns, share one deadline, and meet SE-0526 withDeadline.

Fix 'main actor-isolated property can not be referenced from a nonisolated context' in Swift 6 with four compiled fixes and a snapshot pattern.

SwiftUI .task cancels when the view disappears or its id changes. Cancellation is cooperative — check isCancelled, sleep throws, and onAppear Task does not auto-cancel.

Build a custom AsyncSequence in Swift: why for await pulls values with next(), a paged API example, lazy operators, next(isolation:) and the iterator rules.

3DaysOfSwiftConcurrency.com Free online Swift Concurrency tutorials. What Is the Main Thread? Every iOS application begins with a main thread. The main thread is an execution context used for much of the work that directly affects the application interface. Touch handling, view updates, layout, animation coordination and changes to UI-facing state all depend on the main execution domain remaining available. This is why iOS developers so often discuss blocking the main thread.