The Swift Concurrency Transition I Learned to Love 8 April 2026
There was a period during the Swift Evolution Concurrency discussions that I remember very fondly.
There was a period during the Swift Evolution Concurrency discussions that I remember very fondly.
One of the nice things about Swift Concurrency is its cooperative thread pool. When writting concurrent code you should not think about threads but is still good to know how things work under the hood.
Following Structured Concurrency was one of the best decisions Swift could have made when introducing concurrency into the language. The impact of that decision on all the code written with concurrency in mind can’t be underestimated.
One of the most important aspects to understand about Swift Concurrency is how cancellation of async tasks works. You may expect that when a task is cancelled, it immediately stops, like when you kill a process. But that’s not at all how it works, cancellation in Swift is cooperative.
We’re just in the week of WWDC and it’s clear that Swift’s Concurrency it’s the biggest topic that will change how we develop. I’ve been following its evolution for months now and I’m happy to see how Apple talks about it on their sessions, it helps us see how much they really believe in this new langauge feature.
Swift is about to get its Concurrency features. Their development is going very well, with many proposals actively reviewed and a lot of the work already available in recent snapshots. The story is big and with many moving pieces interlinked with each other. That makes it a bit hard to wrap your head around the entire thing. Specially for those that don’t read Swift Evolution as a hobby ^^.