Eternal Starlight Fix
Java mod listed for Minecraft 1.21. Downloads from the MC Java Mods app on Android.
Performance fix for Eternal Starlight - caches book progression data to eliminate TPS lag caused by repeated data storage hits.
⬇ Download on CurseForgeThe author built this one for Minecraft 1.21.1 on NeoForge. On other versions it may install and then do nothing.
ESFix
A lightweight performance fix for Eternal Starlight.
The Problem
Eternal Starlight's book unlock system calls getOrCreateBookProgressions() for every inventory slot every 200 ticks. Each call hits data storage multiple times with no caching, causing significant TPS lag on servers - especially with multiple players online.
The Solution
ESFix adds a simple mixin that caches book progression data for 5 seconds per player, dramatically reducing data storage access and improving server performance.
Requirements
- NeoForge 1.21.1 - Eternal Starlight
Installation
Drop the jar in your mods folder alongside Eternal Starlight.
- PS Yes, I know the logo is terrible, CF makes me put something there.
- Edition: Minecraft Java
- File type: .jar
- Minecraft version listed: 1.21.1
- How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
- Where to get it: Opens on CurseForge — not every file is mirrored on our own servers.
Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.
- Ships as esfix-1.0.1.jar — drop this file into the mods folder
- Download size: 5 KB
- Download link checked 2 Oct 2026 — working
These come from our own check of the pack file, not from the source page.