So after about 8 months of development I’ve finally got this released. ArmadaCraft is a Minecraft Classic server implementation that is currently a Frankenstein’s monster of 58% Java and 41.8% Kotlin. It supports the following Classic Protocol Extensions:
and also has primitive undocumented unstable unfinished scripting support. It has 4 world generators and a simple save format. There’s still a lot more work to be done, though – it’s probably riddled with bugs.