Fabric Platform

About 261 wordsLess than 1 minute

2026-09-05

Overview

Fabric is the mod's primary target platform, supporting full client + server environments, the Cloth Config GUI, resource pack / data pack generation, and bytecode transformation.

Entrypoints and Load Timing

Entrypoint class: net.luojiayuan.jython.mod.Jythonmod (ModInitializer)
Load timing:
- main (common environment): runs in onInitialize()
- client (client environment): runs in JythonModClient (ClientModInitializer)
- server (server environment): runs in JythonModServer (DedicatedServerModInitializer)
Registered entries are listed in the entrypoints of fabric.mod.json.

In production, Minecraft class names are intermediary (e.g. class_1792). The mod bundles a McReflect import hook, so from net.minecraft.xxx import Yyy is automatically mapped to the runtime class name — no manual handling required.

In the development environment (runClient / runServer), Yarn names are used directly.
In production, names are automatically converted via mappings.tiny (mojmap→intermediary).

Configuration

Cloth Config, config file config/jython-mod.json, supports an in-game GUI.
Dependency declaration: the depends of fabric.mod.json requires cloth-config >= 21.11.153.

Bytecode Transformation

Supported. Transformers registered via BytecodeHelper.registerTransformer() run after Mixin transformation completes (see the BytecodeHelper section of libs.md).

Resource Packs / Data Packs

Supported. The mod automatically extracts resources from the module ZIP to generate resource packs and data packs (see resources.md).

Build and Deployment

./gradlew build

Artifact: build/libs/jython-mod-<version>.jar (bundles the GraalPy runtime, ~56MB).

Deployment: put the JAR in the mods/ folder, put the Python module ZIP in the jymods/ folder, then start the game.

Dependencies: Fabric Loader >= 0.18.4, Fabric API, Cloth Config. See the depends of fabric.mod.json.