Command Structures

Evidence

Ran on Kiln's test stand (2026-11-04): Main did not start: java.lang.NoClassDefFoundError: org/apache/logging/log4j/core/Filter.

What it needs from Kiln

• Mixin
• net.fabricmc.fabric.api.command.v2.CommandRegistrationCallback
• net.minecraft.commands.CommandSourceStack
• net.minecraft.commands.Commands
• net.minecraft.commands.Commands.CommandSelection
• net.minecraft.commands.SharedSuggestionProvider
• net.minecraft.commands.arguments.IdentifierArgument
• net.minecraft.commands.arguments.blocks.BlockInput
• net.minecraft.commands.arguments.blocks.BlockStateArgument
• net.minecraft.commands.arguments.coordinates.Coordinates
• net.minecraft.commands.arguments.coordinates.Vec3Argument
• net.minecraft.commands.arguments.coordinates.WorldCoordinate
• net.minecraft.commands.arguments.coordinates.WorldCoordinates
• net.minecraft.core.BlockPos.MutableBlockPos
• net.minecraft.core.RegistryAccess
• net.minecraft.core.SectionPos
• net.minecraft.network.protocol.game.ClientboundLevelChunkWithLightPacket
• net.minecraft.server.MinecraftServer
• net.minecraft.server.level.ServerChunkCache
• net.minecraft.server.level.ThreadedLevelLightEngine
• net.minecraft.server.packs.resources.ResourceManager
• net.minecraft.server.packs.resources.ResourceManager.Selector
• net.minecraft.world.effect.MobEffectInstance
• net.minecraft.world.effect.MobEffects
• net.minecraft.world.entity.EntitySpawnReason
• net.minecraft.world.entity.EntityType
• net.minecraft.world.entity.Mob
• net.minecraft.world.level.ChunkPos
• net.minecraft.world.level.biome.Climate
• net.minecraft.world.level.biome.Climate.Sampler
• net.minecraft.world.level.block.StructureBlock
• net.minecraft.world.level.block.entity.BlockEntity
• net.minecraft.world.level.block.entity.StructureBlockEntity
• net.minecraft.world.level.block.state.properties.StructureMode
• net.minecraft.world.level.chunk.ChunkAccess
• net.minecraft.world.level.chunk.ChunkGenerator
• net.minecraft.world.level.chunk.LevelChunk
• net.minecraft.world.level.chunk.LevelChunkSection
• net.minecraft.world.level.levelgen.Heightmap
• net.minecraft.world.level.levelgen.Heightmap.Types
• net.minecraft.world.level.levelgen.LegacyRandomSource
• and 52 more

On the roadmap: Minecraft's libraries and client API (0.2), Code next to data (0.3), Machines (0.4), Mixin (0.5)

In the author's words

Spawn Jigsaw Structures by command!

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file command_structures-4.4.5+26.3.jar. The scan reads the mod's classes; it does not run them.