APTweaks: Core (11.x Classic)

The foundation layer of the APTweaks family supplies the code that the other modules call into: an application programming interface, a single place where performance figures are gathered, a unified event system, and command dispatch. Other modules in the set depend on it, so it is installed first and the rest are added on top. Players do not need to install anything, because the mod runs only on the server.

The 11.x Classic line is a stable, long-term branch for existing Forge modpacks, and it targets game versions 1.18.2 – 1.21.1 across 14 release versions. Critical fixes and compatibility updates may still arrive on this branch, while new features, new loader support and newer Minecraft versions go into the all-in-one Adaptive Performance Tweaks release. The project is open source under the MIT License, and its source code and issue tracker are public.

The author describes the core as free of core or mixin patches, which the author presents as a reason for broad compatibility with other mods. Built-in debug information shows what the optimizer is doing, and the modules can be chosen individually through configuration files. The latest Forge file is 11.6.1 for 1.21.1, and a NeoForge file of the same version is published for 1.20.1, both dated 2026-03-10.