Instances of types in Swift, particularly when doing UI programming, are sensitive to retain cycles: A holds on to B and B holds on to A — they're both prevented from being freed. [weak self] to the rescue?

I have an iOS app where I need to know what the latest available iOS version for a given iOS/iPadOS device is, but surprisingly I couldn't find any off-the-shelf solutions. I'm going to publish one myself. I will probably regret this.