A series in chapters

Swift concurrency for GCD hands

A short course for iOS developers who learned concurrency on Grand Central Dispatch. Each chapter starts from the way you would do it with GCD and then shows what Swift concurrency actually does. I’m making the same move myself and write the chapters as I go.

Start with chapter 1

Contents

  1. Chapter 1

    async/await and tasks

    What happens at an await, who runs an async function, and why a semaphore that was harmless under GCD can hang a Swift concurrency app.

    14 min Read

  2. Chapter 2

    Actors and isolation

    What replaces the serial queue, why an actor lets other calls in while it waits, and what @MainActor gives you that main.async never did.

    14 min Read