Worldthreader

Evidence

Ran on Kiln's test stand (2026-11-04): WorldThreaderMod did not start: java.lang.NoClassDefFoundError: net/minecraft/server/MinecraftServer.

What it needs from Kiln

• an access widener
• Mixin
• net.fabricmc.fabric.api.event.lifecycle.v1.ServerLevelEvents
• net.fabricmc.fabric.api.event.lifecycle.v1.ServerLevelEvents.Load
• net.fabricmc.fabric.api.event.lifecycle.v1.ServerLevelEvents.Unload
• net.fabricmc.fabric.api.gamerule.v1.GameRuleBuilder
• net.fabricmc.fabric.api.gamerule.v1.GameRuleBuilder.BooleanRuleBuilder
• net.minecraft.CrashReport
• net.minecraft.CrashReportCategory
• net.minecraft.ReportedException
• net.minecraft.core.Direction.Axis
• net.minecraft.server.MinecraftServer
• net.minecraft.util.profiling.Profiler
• net.minecraft.util.profiling.ProfilerFiller
• net.minecraft.world.level.GameType
• net.minecraft.world.level.gamerules.GameRuleCategory
• net.minecraft.world.level.gamerules.GameRules
• net.minecraft.world.level.storage.PrimaryLevelData
• Reference2ReferenceLinkedOpenHashMap.forEach()
• Reference2ReferenceMap.Entry.getKey()
• Reference2ReferenceMap.Entry.getValue()
• ReferenceSortedSet.removeIf()
• ServerLevel.fillReportDetails()
• ServerLevel.getChunkSource()
• ServerLevel.getLevelData()
• ServerLevel.getServer()
• ServerLevel.tick()
• ServerLevel.tickNonPassenger()
• ServerPlayer.gameMode()
• ServerPlayer.isDeadOrDying()
• ServerPlayer.isRemoved()
• ServerPlayer.wonGame
• Entity.isAlive()
• Blocks.CARVED_PUMPKIN
• Blocks.END_PORTAL_FRAME
• Blocks.REDSTONE_TORCH
• Blocks.WITHER_SKELETON_SKULL

On the roadmap: Minecraft's libraries and client API (0.2), Code next to data (0.3), Mixin (0.5)

In the author's words

Worldthreader speeds up servers by safely running each dimension on a separate thread.

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file Worldthreader-3.2.0.jar. The scan reads the mod's classes; it does not run them.