Fabric Mail

Evidence

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

What it needs from Kiln

• an access widener
• Mixin
• com.mojang.authlib.GameProfile
• net.fabricmc.fabric.api.command.v2.CommandRegistrationCallback
• net.minecraft.TracingExecutor
• net.minecraft.commands.CommandSourceStack
• net.minecraft.commands.Commands
• net.minecraft.commands.Commands.CommandSelection
• net.minecraft.commands.SharedSuggestionProvider
• net.minecraft.nbt.CompoundTag
• net.minecraft.nbt.ListTag
• net.minecraft.nbt.NbtOps
• net.minecraft.nbt.Tag
• net.minecraft.network.chat.ClickEvent
• net.minecraft.network.chat.ClickEvent.RunCommand
• net.minecraft.network.chat.ClickEvent.SuggestCommand
• net.minecraft.network.chat.HoverEvent
• net.minecraft.network.chat.HoverEvent.ShowText
• net.minecraft.network.chat.Style
• net.minecraft.network.chat.TextColor
• net.minecraft.resources.RegistryOps
• net.minecraft.server.MinecraftServer
• net.minecraft.server.Services
• net.minecraft.server.permissions.PermissionLevel
• net.minecraft.server.players.NameAndId
• net.minecraft.server.players.PlayerList
• net.minecraft.server.players.ProfileResolver
• net.minecraft.util.Util
• net.minecraft.world.entity.player.Inventory
• net.minecraft.world.inventory.ContainerInput
• net.minecraft.world.inventory.MenuType
• net.minecraft.world.level.storage.ValueInput
• net.minecraft.world.level.storage.ValueInput.TypedInputList
• org.apache.logging.log4j.Level
• org.apache.logging.log4j.LogManager
• org.apache.logging.log4j.Logger
• MappedRegistry.<init>()
• Component.copy()
• MutableComponent.withStyle()
• ServerLevel.getServer()
• ServerPlayer.getGameProfile()
• ServerPlayer.getInventory()
• and 6 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

Server-sided mod that gives players the ability to leave messages and packages for offline players.

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file fabricmail-2.2.1+26.3.jar. The scan reads the mod's classes; it does not run them.