When working with Minecraft datapacks, JSON logic can quickly become messy, especially when you need precise control over structure placement and overlap rules. Exclusions Lib Mod, compatible with Minecraft 1.21.1 and 1.20.1, is designed to make that process far easier. While regular players won’t notice any visual changes, datapack creators and mod developers will appreciate the cleaner workflow this library provides.
What This Mod Does
Exclusions Lib is a lightweight library that adds advanced block predicates for datapacks, including the powerfulexclusions_lib:overlaps_structure check. This lets you exclude block generation in specific structures or areas, such as preventing ores from spawning inside villages or custom builds. Instead of juggling complicated JSON workarounds, you can write simple, readable conditions.
The mod supports Fabric, Forge, and Quilt, and it’s server-side only, meaning players don’t need to install it unless another mod directly depends on it.
Key Features
- Adds
overlaps_structurepredicate for structure-aware block placement - Reduces complexity in datapack JSON logic
- Works with vanilla and modded structures
- Fully compatible with Fabric, Forge, and Quilt loaders
- Server-only installation for dependency management
Screenshots:
Why It Matters
Anyone who has built datapacks knows how painful it can be to manage structure logic in JSON. One datapack creator on Reddit described JSON predicates as “a constant headache when trying to control world-gen behavior.” Exclusions Lib tackles exactly that pain point, making world-gen control both more precise and easier to maintain.
For server admins, this also means fewer datapack conflicts and cleaner performance, since redundant or conflicting generation rules can be avoided entirely.
My Experience
I tested this mod on a Fabric server running custom datapacks, and the difference was immediate. Tasks that normally required long JSON chains were reduced to a single, clear predicate. It’s not a flashy mod, but it saves hours of debugging and troubleshooting.
Requires:
How to install:
How To Download & Install Mods with Minecraft Forge
How To Download & Install Fabric Mods
How To Download & Install The Quilt Loader
Download links
- Forge Version:download Download file
- Fabric Version:download Download file
- Fabric Version:download Download file
