A few of the 5.9 changes as summarized on the Hacking With Swift blog.

Macros seem very powerful, and Apple has been immediately putting them to prominent use in new framework such as SwiftData.

My interest is also piqued by the changes that allow for variadic generics, thus finally allowing for more than 10 views in SwiftUI.

What are some of the changes in 5.9 that interest you the most?