Concurrent Chunk Management Engine - Forge

C2ME-Forge 0.2.0-forge.9.6 (Minecraft 1.20.1) - build 2026-09-19

Hotfix for forge.9.5: block-entity data written after a chunk unload. Nothing else. No worldgen changes, existing worlds unaffected.

Fixed
• Block entities could be saved from a state their mod had already torn down. When a chunk unloads, C2ME writes the chunk file on a worker thread, and it produced each block entity's NBT there, after the server thread had already removed every block entity in the chunk; vanilla writes that NBT before the removal. A mod that clears state when a block entity is removed therefore saved empty data under C2ME. Copycats+ does this for all of its multi-state blocks (slabs, stairs, panels and the rest of its shapes): the block placed inside came back as the plain copycat after every unload and reload, while force-loaded chunks kept it. C2ME now writes every block entity's NBT on the server thread at the moment the save is scheduled, exactly when vanilla would, and the worker only copies it into the chunk file. Covers both of C2ME's serializer paths and every mod, not only Copycats+

Drop-in update - recommended for everyone on forge.9.x, and required if you use Copycats+. No config changes needed.
Support: https://discord.gg/s7BYs6Njj5