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Hello,I'm currently trying (in Swift, iOS 13+) to reproduce an end to end communication mechanism inspired by apps like SignalApp or iMessage. But there is something I don't see how to do. When encrypting a new message the idea for a better forward secrecy and post-compromise security implies the use of not 1 but 3 or 4 DH shared secrets to compute the symmetric key (here is the part of the SignalApp protocol documentation that explains that part https://signal.org/docs/specifications/x3dh#sending-the-initial-message). But I don't think this is currently possible with CryptoKit since I don't see any way to combine multiple CryptoKit.SharedSecret together. Or am I missing something ?I could use a third party library for that of course, but I would rather not if it's possible.Thank you ! (and sorry for my english :s)