Gradle Dependency Setup

MBD2 21.1.1

Use the FirstDark snapshots repository to compile a NeoForge 1.21.1 mod against MBD2.

gradle.properties

minecraft_version=1.21.1
neo_version=21.1.238
mbd2_version=21.1.1
ldlib2_version=2.2.39.a

Pin LDLib2 explicitly: Java extensions import its annotations, configurators, UI classes and sync APIs directly, and MBD2's own declared range ([2.2.39.a,)) is a lower bound, not a pin.

Groovy build.gradle

repositories {
    maven {
        name = "FirstDark snapshots"
        url = uri("https://maven.firstdark.dev/snapshots")
    }
}

dependencies {
    implementation("com.lowdragmc.multiblocked2:" +
            "Multiblocked2-1.21-${minecraft_version}:${mbd2_version}")

    implementation("com.lowdragmc.ldlib2:" +
            "ldlib2-neoforge-${minecraft_version}:${ldlib2_version}:all")
}

The MBD2 artifact name contains both the branch family (1.21) and the exact Minecraft version (1.21.1), so the resolved coordinate for the values above is:

com.lowdragmc.multiblocked2:Multiblocked2-1.21-1.21.1:21.1.1

Do not use the 1.20.1 coordinate com.lowdragmc.multiblocked2:Multiblocked2:<minecraft>-<version>.

Kotlin DSL

repositories {
    maven("https://maven.firstdark.dev/snapshots") {
        name = "FirstDark snapshots"
    }
}

dependencies {
    implementation(
        "com.lowdragmc.multiblocked2:" +
            "Multiblocked2-1.21-${property("minecraft_version")}:" +
            property("mbd2_version")
    )
    implementation(
        "com.lowdragmc.ldlib2:" +
            "ldlib2-neoforge-${property("minecraft_version")}:" +
            "${property("ldlib2_version")}:all"
    )
}

What MBD2 itself requires

Requirement	21.1.1
Minecraft	1.21.1
Java toolchain	21
NeoForge	Built against 21.1.238; declared range [21.1.217,)
LDLib2	2.2.39.a; declared range [2.2.39.a,) — required
KilaGraph	21.1.0.13; declared range [21.1.0.12,) — required, jar-in-jar'd
Photon	2.2.5+ — optional, needed only for machine effects
Mod ID	mbd2

java {
    toolchain.languageVersion = JavaLanguageVersion.of(21)
}

KilaGraph is bundled inside the MBD2 jar, so you do not declare it — but if your extension adds blueprint nodes, add it to compileOnly at the same version.

Optional integration APIs

The core dependency is enough for machine, recipe, Trait and condition extensions. Add an integration mod to compileOnly only when your source imports that mod's API, and to the development runtime when you need to launch and test it.

dependencies {
    // Example pattern; use the integration's official coordinate and version.
    compileOnly("mekanism:Mekanism:${mekanism_version}:api")
    runtimeOnly("mekanism:Mekanism:${mekanism_version}")
}

Guard optional registration with @LDLRegister(modID = "...") or a loader check. compileOnly prevents bundling; it does not prevent a NoClassDefFoundError from an unguarded class that references a missing mod.

Verify that the guard works

Configure a run that removes the optional mod from the runtime classpath and launch it. MBD2 does exactly this for Photon and PneumaticCraft — an absent-mod run is the only thing that proves a soft dependency is really soft.

Verify resolution

./gradlew.bat dependencies --configuration compileClasspath
./gradlew.bat compileJava

Confirm the report contains exactly one MBD2 and one compatible LDLib2. If the IDE still shows unresolved MBD2 packages, refresh the Gradle project.

Distribution

Do not shade or relocate MBD2 or LDLib2 into your mod. Declare them as required dependencies in neoforge.mods.toml.