ScalableLux (Unofficial Backport)

An independent Fabric 1.20.1 backport of ScalableLux’s Starlight-based lighting engine, based on upstream 0.1.0.1 for Minecraft 1.21.1 and adapted for the older chunk and lighting APIs.

Features

• Starlight-based block and sky lighting.
• Configurable parallel light updates for supported workloads.
• Client and dedicated-server support.

Requirements and installation

• Minecraft 1.20.1, Java 17 or newer, and Fabric Loader 0.15.11 or newer.
• MixinExtras 0.3.5 or newer is required; the mod metadata declares this dependency.
• Install on both client and server for multiplayer.
• Do not combine with Phosphor or another mod that replaces the light engine.
• Back up worlds before testing any lighting-engine replacement.

Verification

The release passed four targeted Minecraft 1.20.1 Fabric GameTests with both one and four configured light workers. They cover block-light propagation and removal across a chunk border, skylight roof changes, lighting-data serialization, and asymmetric positive and negative chunk lookups. A separate client-startup smoke test applied the client and server light-engine mixins. This does not guarantee compatibility with every modpack or lighting interaction; no benchmark claims are made.

Upstream and license

This is an unofficial, independently maintained backport and is not affiliated with or endorsed by the upstream authors. It is based on RelativityMC/ScalableLux, licensed LGPL-3.0-only. The JAR also includes the MIT license for its embedded FlowSched component. The upstream icon is not redistributed; this project uses an original logo.

Source and support

Browse the complete port source on GitHub. Report backport-specific issues here.

The backport code, release description, and original project logo were prepared with AI assistance; this disclosure does not describe the upstream authors’ work.