The custom seed not being applied to the runtime world has been fixed by #22.
When entering the world after the first server start everything works fine (/seed gives the correct seed).
However, after restarting the server, the runtime world has the server seed (/seed gives the server seed) and proceeds to generate new chunks with it.
This also happens when closing and reopening singleplayer worlds.
This is because RuntimeWorld#getSeed is responsible for returning the custom seed but after a restart the world is loaded by Minecraft as a ServerWorld.
The custom seed not being applied to the runtime world has been fixed by #22. When entering the world after the first server start everything works fine (
/seed
gives the correct seed). However, after restarting the server, the runtime world has the server seed (/seed
gives the server seed) and proceeds to generate new chunks with it. This also happens when closing and reopening singleplayer worlds.