KBVE Behavior StateTree
by h0lybyte
KBVE Behavior StateTree is a Fabric library that runs behavior state machines for Minecraft Java Edition mods, with its core written in Rust and called through JNI.
What it does
The library moves heavy behavior logic off Minecraft's main thread and uses an ECS-style framework, modeled on the approach the Hytale game takes with its FLECS ECS. Behavior trees are built from queries, and the runtime provides multi-threading. A layer between Java and Rust passes data across the boundary. Fabric API is required. The license is custom and the project is not open source, though its source code is public.
Files target 1.21.11 only, with 1.0.67 published on 2026-07-11 as the latest build, after a first release on 2026-04-17. The library is built for Fabric, and its core plugin is a separate component that the library works with.
Key features
Behavior state machine
A state machine written with Bevy Rust drives behavior, and the Rust code runs through JNI.
ECS-style behavior trees
Behavior trees are built from queries in an ECS-style structure that keeps logic organized.
Off-thread heavy logic
Heavy logic is moved away from Minecraft's main thread, with multi-threading provided by the runtime.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Requirements
Dependencies declared by the latest file for each loader.
Required 1
Questions
Does KBVE Behavior StateTree need Fabric API?
What the author says
This is a behavior state machine that is written using Bevy in Rust, then ran using JNI. The objective is to build out an open source foundation of ECS-style behavior trees using queries with the aim of moving the heavy logic off the minecraft's main thread. This is an ECS framework, that we are using in a similar…
Official listing
- Modrinth page
- modrinth.com/mod/kbve-behavior-statetree
- Owner
- h0lybyte
- Published
- 2026-04-17
- Updated on Modrinth
- 2026-07-11
- Facts verified
- 2026-10-15