Swift 3 is compatible with iOS8. why the library needs iOS9 ?
Yeah, I think it would be nice if we support past 3 iOS versions (8,9,10) if possible.
You can see issue #1367 for a full explanation of why we aren't.
The reason why they target IOS 9 is supporting URLSessionStreamTask. I created a fork https://github.com/tonyli508/AlamofireDomain which disabled URLSessionStreamTask, and will pull the latest changes from time to time.
That is not why. See #1367 for more details and be forewarned, your fork likely isn't reimplementing the various workarounds we had for iOS 8 bugs.
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Yeah, I think it would be nice if we support past 3 iOS versions (8,9,10) if possible.