ARLib

My multiblock, GUI, networking & rendering lib. Free Minecraft Java mod for 1.21.1, 1.21.

Which Minecraft do you have?

Every version of the game needs its own build. Pick yours, then download — the wrong build installs fine and then does nothing in the game. This mod is built for NeoForge only.

Minecraft 1.21.1Newest
Minecraft 1.21

⬇ Download for 1.21.1 ⬇ Download for 1.21

I don't know my version or loader

Open the Minecraft launcher and look at the profile you play on — it names both, like fabric-loader-1.21.4. The version also shows in the bottom-right corner of the game's main menu.

No loader in the profile name? Then it's plain Minecraft, and these mods won't run — you need Fabric or NeoForge installed first.

Open in MC Java Mods Get it on Google Play →

ARLib 1.21.1 contains

logic for multiblock structures
logic for recipe management / loading from xml,
simple modular GUIs
simply networking interface for nbt based networking
.obj model loader for BlockEntity renderer
some shader overwrites to patch in NormalMat and UVOffset uniforms

1.12.2 repo: dercodeKoenig/libVulpes-fork2

1.21.1 repo: dercodeKoenig/ARLib-neoforge-1.21

Verified by MCModsHub

Ships as arlib-1.0.0.jar — drop this file into the mods folder
Download size: 174 KB
Download link checked 27 Aug 2026 — working

These come from our own check of the pack file, not from the source page.

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