CRBuild

A build and development tool for Minecraft Cleanroom mods.

Features

• Download and set up the Cleanroom development environment
• Build mods (Java / Kotlin / Scala, with incremental compilation)
• Launch dev client / server
• Generate decompiled sources for IDE attachment
• Scaffold new mod projects
• Publish to Maven

Commands

crbuild init          # Create a new project
crbuild setup         # Download dependencies, compilers, generate dev jar
crbuild build         # Build and package (dev jar + production jar)
crbuild run-client    # Build and launch dev client
crbuild run-server    # Build and launch dev server
crbuild gensources    # Generate decompiled source jar
crbuild publish       # Publish to Maven
crbuild locale        # View or switch locale (en-US | zh-CN)

Build from Source

Requirements: Rust toolchain (2024 edition), JDK 25.

cd crbuild
cargo build --release

Output: target/release/crbuild.

The Worker (JVM subprocess) is automatically extracted from the built crworker.jar on first crbuild setup. To build it separately:

cd crbuild/worker
./gradlew shadowJar

Configuration

crbuild.toml in the project root, generated by crbuild init, editable manually.

Main sections:

• [mod] — Mod info (id, version, name, group, authors)
• [build] — Build options (generate_sources, generate_javadocs, shadow)
• [run] — Run configuration (username, jvm_arg)
• [fml] — FML configuration (access transformer, coremod, mixin)
• [dependencies] — Dependencies (compile_only, mod_implementation, contain, repositories)
• [language] — Language settings (kotlin, scala version)
• [publishing] — Maven publishing configuration