Nevyn Bengtsson with a video and introductory post on his CoreDragon library. It really feels like this is something that might be introduced to the iOS 10 API as split screen multitasking matures, but why wait until (if!) that happens when you can implement it right now. There's also a couple of demo apps here if you want to test it out.
Ambitious project from Jake Lin which aims to allow much more customisation of views, and animations on those views directly inside Interface Builder. The best thing about this is that it has been entirely built on top of @IBDesignable and @IBInspectable so there's no plugins or other tools needed. It's also worth noting that this isn't the first time something like this has been done. I thought I had linked to Spring and CanvasPod before but searching through the archives it seems I didn't! Apologies for that.
Fun little library from Joachim Bondo for calculating a list of edits to transform one set of data into another. It was originally intended to help with performing non trivial changes of state in a table/collection view, but I can see this could have other uses as well.
I'm really enjoying this series of posts by Ankit Agarwal digging into the depths of Swift. Last week was Arrays and this week its the turn of the Builtin module.