title: Binary compatibility of different versions of Swift
body: <p>We are developing an iOS framework using Swift 2.2. This framework is intended for outside use, i.e., its built binary will be distributed to our clients, and they will use it to develop their applications.</p>
  
  <p>Another update: Swift 3 will not have ABI compatibility. See here: <a href="https://www.infoq.com/news/2016/05/swift-3-no-stable-abi" rel="nofollow">https://www.infoq.com/news/2016/05/swift-3-no-stable-abi</a>.</p>
  
  <p>So if we author the framework in Swift, and the only way to guarantee our clients using different versions of Swift can consume it safely is to build multiple versions of the framework, and ask them to download the version that matches theirs, right?</p>