This is an invitation for discussion about the [Crypto](https://github.com/softwaremill/akka-http-session/blob/master/core/src/main/scala/com/softwaremill/session/Crypto.scala) implementation ported from Play Framework and its future. Here's the [issue that led to deprecation of the Crypto API from Play](https://github.com/playframework/playframework/issues/4407) and [here is migration guide in Play 2.5](https://www.playframework.com/documentation/2.5.x/CryptoMigration25#Crypto-Migration-Guide). I don't know much about cryptography, so unfortunately I can't say anything more useful.