ModsJava
Lost Libraries
Java mod listed for Minecraft 1.20–1.21. Downloads from the MC Java Mods app on Android.
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.
Ancient libraries lay buried, forgotten by time. Magic books are abundant.
Features
New Structure: The lost library generates underground. It has a lot of bookshelves, maybe some are salvageable? Also has anvils, a lodestone, a smithing table, and a potion station.
Compatibility
Spawns using the #is_overworld tag, so should be compatible with anything. Uses stronghold library loot, so changing that will change the loot that appears in this structure.
REQUIRES COMMAND BLOCKS
Quick facts
- Edition: Minecraft Java
- File type: .jar
- Minecraft versions listed: 1.21, 1.21.4, 1.21.3
- 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.
File checked by MCModsHub
- Ships as lost-libraries-1.1.2.jar — drop this file into the mods folder
- Download size: 31 KB
- Download link checked 26 Sept 2026 — working
These come from our own check of the pack file, not from the source page.