YUNG's API Mod (1.21.4, 1.20.4) – Library for YUNG's mods.

YUNG's API is a library mod that provides essential shared code and utilities for all of YUNG's popular Minecraft mods, available for Fabric, Forge, and NeoForge mod loaders. If you want to run any mod from the YUNG's series — such as Better Dungeons, Better Strongholds, or Better Caves — this API must be installed as a required dependency.

If you have ever tried to install a YUNG's mod and hit a crash screen telling you a dependency is missing, YUNG's API is the piece you are looking for. As a library mod, it does not add blocks, items, or visible changes to your game on its own. Instead, it supplies the underlying framework — world generation tools, registration systems, and data utilities — that all of YUNG's structure-overhaul mods rely on. With over 24 million downloads on Modrinth alone, it is one of the most widely depended-upon library mods in the entire Minecraft modding ecosystem. That download count is not driven by hype; it is driven by the sheer number of players who run at least one YUNG's mod in their modpack and need this API to make it work.

Key Features of YUNG's API

• AutoRegistration System (1.18+) — For mod developers, this is a game-changer. Instead of writing loader-specific registration code for Fabric, Forge, and NeoForge separately, a simple annotation handles it all. This means YUNG's mods can ship cross-platform updates faster, which directly benefits players who want the same mod on any loader without long waits between ports.
• Custom Jigsaw Manager — Vanilla Minecraft's Jigsaw system handles how structure pieces connect together, but it has performance limitations. YUNG's API replaces it with an improved implementation that offers better performance and supports custom pool element types with new properties. This is the engine behind the impressive procedural dungeons and structures in mods like Better Dungeons and Better Ocean Monuments.
• Safe Structure Location Trigger — Vanilla Minecraft has a known issue where trying to locate a structure that does not exist in your world can cause the advancement trigger to instantly pass instead of failing gracefully. YUNG's API provides a safer criteria trigger that simply fails if the structure is missing, preventing false completions and potential bugs in modded advancement chains.
• BlockStateRandomizer & ItemRandomizer — These data abstractions make it simple for mod developers to add randomized block palettes and item loot to generated structures. For players, this translates directly into more visually varied dungeons and ruins — you will not see the same stone brick pattern repeated identically in every room.
• JSON Serialization Interfaces — Built-in type adapters for JSON serialization and deserialization allow YUNG's mods to load configuration and structure data efficiently. This keeps mod file sizes small and loading times short, which matters in large modpacks where dozens of mods compete for startup time.
• Lightweight Math Utilities — Simple vector and column position math utilities keep world generation calculations fast without pulling in heavy external libraries. The API appears to be lightweight in terms of runtime footprint, adding minimal overhead to your game even when multiple YUNG's mods are active simultaneously.

Screenshots

How to Install YUNG's API

1. Choose your mod loader. YUNG's API supports Fabric, Minecraft Forge, and NeoForge. Make sure your loader is already installed for your Minecraft version.
2. Download the correct version of YUNG's API for your Minecraft version and loader from the download section below. For Minecraft 1.21.4, Fabric and NeoForge builds are available. For 1.21.1 and older, Forge builds are also available.
3. Place the downloaded .jar file into your .minecraft/mods folder. If the folder does not exist, launch Minecraft once with your mod loader selected to generate it.
4. Download whichever YUNG's mods you want to use — such as YUNG's Better Dungeons or YUNG's Better Strongholds — and place them in the same mods folder.
5. Launch Minecraft. The API loads silently in the background. If everything is working, the YUNG's mods you installed will function without errors.

Requirements & Compatibility

What's New

• Added helper methods to AutoRegisterEntityType.Builder, including support for passenger attachment points that mirror vanilla behavior.
• Introduced getHolder() methods for AutoRegister MobEffect and Potion, resolving registry issues that could occur on Forge and NeoForge.
• AutoRegisterPotion now accepts a Potion supplier for consistency with other AutoRegister wrapper classes.
• Updated AutoRegisterUtils.registerBrewingRecipe() to use Holders as parameters instead of Suppliers, improving type safety.

Pros and Cons

Alternatives to YUNG's API

• Cloth Config API — A widely used configuration library mod that many other mods depend on. If you are building a modpack, you will likely need this alongside YUNG's API for other mods in your list.
• Architectury API — A cross-platform abstraction layer that helps mod developers write code once and deploy to Fabric, Forge, and NeoForge. Serves a similar multi-loader purpose but for a broader range of mods.
• GeckoLib — An animation library mod required by many mods that add custom entities and creatures. Like YUNG's API, it is a behind-the-scenes dependency rather than a standalone gameplay mod.

Download YUNG's API

Always download mods from official sources to stay safe.

Frequently Asked Questions

Do I need YUNG's API if I only use one YUNG's mod?

Yes — every YUNG's mod requires YUNG's API regardless of how many you use. Even if you only install a single mod like YUNG's Better Mineshafts, the API must be present in your mods folder or the game will crash on startup.

Does YUNG's API add anything visible to my Minecraft world?

No, it adds nothing visible on its own. YUNG's API is purely a behind-the-scenes library that provides shared code, world generation utilities, and registration systems. The visual changes come from the individual YUNG's mods that depend on it.

Is YUNG's API compatible with Minecraft 1.21.4?

Yes — YUNG's API supports Minecraft 1.21.4 on both Fabric and NeoForge. However, Forge is not available for 1.21.4, so Forge users will need to stay on 1.21.1 or switch to NeoForge for the latest version.

Can I use YUNG's API with OptiFine or Sodium?

Generally yes — since YUNG's API is a library focused on world generation utilities and registration, it does not conflict with rendering mods like Sodium or OptiFine. There are no widely reported incompatibilities between them.

Does YUNG's API affect game performance?

The impact appears to be negligible for players. As a library mod, it only runs code when the YUNG's mods that depend on it actively call its functions. Its custom Jigsaw Manager is actually designed to improve structure generation performance compared to the vanilla system, so in practice it may help rather than hurt.

You May Also Like

NeoForge Mod (1.21.11, 1.21.1) – TaCZ NeoForge

1 week ago

Timeless and Classics Zero NeoForge Mod (1.21.1) – TaCZ NeoForge

1 week ago

Alternate Current Mod (1.21.11, 1.20.6) – An Efficient Redstone Dust

5 days ago

Just Enough Items Mod (1.21.11) – JEI, Crafting Recipes Viewing

1 week ago

Ocean's Delight Mod (1.21.1, 1.20.1) – Ocean Cooking Expansion

4 days ago

2032 World Height Mod (1.20.1) – From Ground Level To Sky High

7 days ago