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forgematica Patch Mod

Forgematica Patch for NeoForge 21.1.235 Fixes IllegalAccessError caused by private access to BufferBuilder.building.

NeoForge
Loaders
NeoForge
Downloads on Modrinth
3.1K
Followers on Modrinth
1
version
1
Updated
July 11, 2026Jul 11
Published
in 2026

At a glance

Runs on NeoForge
For Minecraft 1.21.1
Client only — no need to install it on the server
Latest version — 1.0.0 from July 11, 2026
Requires MaFgLib and Forgematica
License Apache-2.0 — free
Where it's needed
In gamerequiredOn servernot needed

Install in the game only; not needed on the server

Game versions1.21.1

Forgematica Patch

This mod restores compatibility between Forgematica 0.4.2 and NeoForge 21.1.235.

Without this patch, loading a schematic causes Forgematica to crash with an IllegalAccessError caused by access to the private BufferBuilder.building field.

The patch uses a small Mixin compatibility layer without modifying Forgematica itself.

Requirements

Problem

Without this patch, loading a schematic causes Forgematica to crash with:

java.lang.IllegalAccessError:
class fi.dy.masa.litematica.render.schematic.BufferBuilderCache tried to access private field
com.mojang.blaze3d.vertex.BufferBuilder.building

This patch resolves the compatibility issue on NeoForge 21.1.235.

Solution

This patch restores compatibility between Forgematica 0.4.2 and NeoForge 21.1.235.

Notes

This is a compatibility patch only.

It does not add new features or change Forgematica's functionality.

It does not modify any Forgematica files.

It can be removed at any time without affecting your worlds or schematics.

FAQ

How to install forgematica Patch Mod?

Install NeoForge for your Minecraft version, download forgematica Patch Mod for the same version and loader, put the file into the mods folder and launch the game with the loader profile.

Which Minecraft versions does forgematica Patch Mod support?

forgematica Patch Mod has builds for Minecraft 1.21.1.

Is forgematica Patch Mod needed on the server?

Client only — no need to install it on the server

License and source
Apache License 2.0free to use and share with credit to the author
Original — Modrinth↗Files unchanged, verified with SHA-512Is this your mod? For rights holders

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