Lithium is a general-purpose optimization mod for Minecraft which works to improve a number of systems (game physics, mob AI, block ticking, etc) without changing any behavior. It works on both the client and server, and can be installed on servers without requiring clients to also have the mod. With the mod installed, you can see on average a 45% improvement to server tick times, resulting in a much leaner game.
Now with OptiLithium you're now able to use OptiFabric (Optifine) and lithium together.

