JamLib

Evidence

Ran on Kiln's test stand (2026-11-04): JamLibFabric did not start: java.lang.NoSuchMethodError: 'java.util.Optional net.fabricmc.loader.api.FabricLoader.getModContainer(java.lang.String)'; JamLibClientFabric did not start: java.lang.NoClassDefFoundError: net/minecraft/network/codec/ByteBufCodecs.

What it needs from Kiln

• Mixin
• io.netty.buffer.Unpooled
• net.fabricmc.fabric.api.client.command.v2.ClientCommandRegistrationCallback
• net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking
• net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking.Context
• net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking.PlayPayloadHandler
• net.fabricmc.fabric.api.command.v2.CommandRegistrationCallback
• net.fabricmc.fabric.api.networking.v1.PayloadTypeRegistry
• net.fabricmc.fabric.api.networking.v1.ServerPlayNetworking
• net.fabricmc.fabric.api.networking.v1.ServerPlayNetworking.Context
• net.fabricmc.fabric.api.networking.v1.ServerPlayNetworking.PlayPayloadHandler
• net.fabricmc.loader.api.ModContainer
• net.fabricmc.loader.api.Version
• net.fabricmc.loader.api.metadata.ModMetadata
• net.minecraft.commands.Commands
• net.minecraft.commands.Commands.CommandSelection
• net.minecraft.network.FriendlyByteBuf
• net.minecraft.network.RegistryFriendlyByteBuf
• net.minecraft.network.codec.ByteBufCodecs
• net.minecraft.network.codec.StreamCodec
• net.minecraft.network.codec.StreamCodec.CodecOperation
• net.minecraft.network.codec.StreamDecoder
• net.minecraft.network.protocol.common.custom.CustomPacketPayload
• net.minecraft.network.protocol.common.custom.CustomPacketPayload.Type
• net.minecraft.network.protocol.common.custom.CustomPacketPayload.TypeAndCodec
• FabricLoader.getModContainer()
• FabricLoader.isDevelopmentEnvironment()
• ClientLevel.registryAccess()
• ServerLevel.registryAccess()

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

The platform-agnostic, Architectury based library used in all of JamCoreModding's mods

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file jamlib-fabric-2.3.1+26.3.x.jar. The scan reads the mod's classes; it does not run them.