Comment by kaylynb

Chunk gen makes sense to implement last or never. If you want a performant Minecraft server you need to pregen all the chunks anyway. You can still later regen chunks that have never been visited to get new chunkgen on updates since chunks store the inhabited time.

I think Minecraft server re-implementations are pretty neat and I like to see when a new one comes out. There are also specific purpose server impls like MCHPRS for doing fast redstone compilation for technical minecraft.