Description
Prefab ships with a handful of buildings. After a while you get bored of them.
This addon adds an extension pack system: press Z in-game to browse and download community-made packs, or press X to make your own.
Downloader — browse community packs, pick one, drops into prefab-extension/, ready to use next time you load a world.
Creator — local workspace mode. Fill in a form, pick an NBT, pick a cover image, a few clicks and you have a standard extension pack (with ZIP). Everything lives in prefab-work/ at your game root. Export NBT files using the vanilla Structure Block.
Requires: Prefab 1.0.7+, LDLib2 2.2+. Tested on NeoForge 21.1.233 / MC 1.21.1 / Java 21+.
Keybindings
| Key | Action |
|---|---|
| Z | Open extension pack downloader |
| X | Open extension pack creator |
Folder Layout
The workspace folder mirrors the published pack format:
prefab-work/
├── <pack_id>/
│ ├── information/
│ │ ├── <pack_id>.txt
│ │ └── cover.png
│ └── construction/
│ ├── <building_id>.nbt
│ ├── <building_id>.png
│ └── <building_id>.txt
└── <pack_id>.zip ← auto-generated
Any change under prefab-work/<id>/ triggers an automatic repack into prefab-work/<id>.zip. To install a pack manually, unzip the file into prefab-extension/<id>/.
Dependencies
| Mod | Version | Required | Purpose |
|---|---|---|---|
| Prefab | 1.0.7+ | yes | core — provides GuiStructure, BuildBlock, etc. |
| LDLib2 | 2.2+ | yes | UI utilities |
NeoForge 21.1.233 on Minecraft 1.21.1.


