Hello. Thanks for the great framework! I was thinking about contributing client certificate authentication to ktor. This is case that I really miss and I believe it is required in many enterprise setups out there. I've already implemented it (as a patch) for my setup (I use ktor-server-netty). But can try and extend it to all other server implementations in phase 1 and then add the support to ktor clients in phase 2. Would really like to know what you think about it. Thanks!