Concurrent Chunk Management Engine (Fabric)

What it does C2ME (Concurrent Chunk Management Engine) is a Fabric mod that rewrites how Minecraft handles chunk generation, I/O, and loading so those tasks can run across multiple CPU cores at the same time. The goal is to make world generation and chunk loading scale with the hardware you have instead of staying stuck on a single thread. It targets the parts of the pipeline that normally bottleneck when you explore new terrain or run heavy datapacks. ## Vanilla parity The mod doesn't change vanilla world generation or behavior by default. Worlds generated with the same seed will still vary run-to-run because vanilla generation itself is non-deterministic, but C2ME doesn't add its own alterations. If a difference from intended vanilla behavior appears, the authors treat it as a bug and ask that you report it. ## Compatibility Vanilla world-generation datapacks work fully. Custom world generators from other mods usually run, but they can hit compatibility issues when those mods rely on design assumptions that C2ME breaks for the sake of speed. The authors are open to helping generator authors adapt. The mod also includes a CheckedThreadLocalRandom implementation (part of UWRAD) and a few other sanitizers that catch undefined behavior in other mods; these detections rarely produce false positives and should be reported to the offending mod's author. ## Version support Only the latest Minecraft release and the latest snapshot receive full support. Older releases are in long-term support and get critical bug fixes. Older snapshots aren't supported. The Modrinth record lists supported versions including 1.21.1, 1.21.11, and several 26.x snapshots. ## Sides and loaders The mod runs on Fabric only. It's optional on the client and required on the server. ## Recommendations For best results the authors suggest pairing C2ME with Lithium and ScalableLux. Back up your worlds before adding any world-generation mod.