Concurrency

Swift offers actors, GCD, and locks for thread safety. Each solves the same problem differently. Here's how to choose.

Actors provide compile-time safety for shared mutable state in Swift. Here's when to use them and how they compare to older approaches.

Grand Central Dispatch remains a practical choice for thread safety in Swift, especially when you need synchronous access or are working with legacy code.

Locks offer the lowest overhead for thread synchronization in Swift. Here's when that matters and how to use them safely.

Before Swift closures, Objective-C had blocks. The syntax is different, but the power is the same—here's how to use them effectively.

Learn how dispatch barrier queues provide elegant reader-writer synchronization in Objective-C without explicit locks or semaphores.