ModsFinder

prefab-custom-addon

by veyne

Prefab, a NeoForge addon for Minecraft 1.20.1 and 1.21.1, lets players add custom building extension packs, with a browser for community-made packs and a local creator workspace.

ForgeNeoForgeClient and serverMIT LicenseOpen source1.20.1 – 1.21.1

What it does

Prefab ships with a handful of buildings, and its extension pack system lets players add more. Pressing Z in-game opens a downloader where community-made packs can be browsed and chosen; a chosen pack is saved as a prefab-extension and is ready to use the next time a world loads. Pressing X opens the creator, a local workspace mode for making a pack of one's own.

In the creator, a form takes a name, an NBT file, a cover image and a few further entries, which produces a standard extension pack. Everything the creator produces lives in the prefab-work folder inside the game root. Structures are exported as NBT files using the vanilla Structure Block. A pack can also be installed by hand by unzipping the file into prefab-extension.

Prefab requires LDLib, and the combination tested on NeoForge for Minecraft 1.21.1 with Java 21 uses LDLib2 2.2 or newer. The mod works with a dedicated server, and its environment is client and server.

Key features

  1. Community pack browser

    The Z downloader lists community-made extension packs, and a chosen pack is added to prefab-extension for later use.

  2. Pack creator

    The X creator fills a form from an NBT file and a cover image to produce a standard extension pack.

  3. Workspace auto-repack

    Changes in the prefab-work folder are repacked automatically into a ZIP, matching the published pack format.

  4. Manual pack install

    A pack can be installed by unzipping it into the prefab-extension folder without using the downloader.

Compatibility

Latest build for each game version and loader.

1.21.1Not available2.7.1
1.20.12.1.0Not available
ReleaseBetaAlphaNot available

Only full game releases are shown. This mod publishes no snapshot builds.

Requirements

Dependencies declared by the latest file for each loader.

Required 2

PrefabProvides items for automatically generating buildings in the world
Required
LDLibLDLib is a libarary mod for custom rendering, modular gui.
Required

Use cases

Who it’s for: Players who run out of the included buildings and want extra packs, and creators who build structures and want to share them as extension packs. Server owners need the mod on the server and on every client that connects.

Questions

Which loaders does Prefab support?

Prefab is published for Forge and NeoForge. The files for 1.20.1 are Forge builds, and the files for 1.21.1 are NeoForge builds, with the latest NeoForge file being 2.7.1 for 1.21.1.

Does the server need Prefab installed?

Yes. Installation covers the server and each player's game.

Does Prefab need LDLib to run?

Yes. LDLib is a required dependency, and the tested combination uses LDLib2 2.2 or newer.

Where do packs made in the creator end up?

They are kept in the prefab-work folder inside the game root, which is repacked automatically into a ZIP whenever a change is saved there.

In the catalog

prefab-custom-addon is one of 8,016 Management mods on ModsFinder, and one of 2,698 Management mods for Forge. 32,366 mods support Minecraft 1.21.1.

Management mods8,016Forge modsMods for 1.21.132,366

Similar mods

Cherished Worlds1.12.2 – 26.3Default Options1.18 – 26.3Resourcify1.8.9 – 26.3Rebind Narrator1.16.1 – 26.1.2Paxi1.19.2 – 26.1.2Starter Kit1.16.5 – 26.3

What the author says

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.
veyne, on the Modrinth page

Official listing

Owner
veyne
Published
2026-06-15
Updated on Modrinth
2026-10-15
Facts verified
2026-10-15

Tags

DecorationManagementUtility
Open on ModrinthCompare