Polymer - Quality of Life

Evidence

Ran on Kiln's test stand (2026-11-04): PolymerQOL did not start: java.lang.NoClassDefFoundError: net/minecraft/network/protocol/common/custom/CustomPacketPayload; PolymerQOLClient did not start: java.lang.NoClassDefFoundError: net/minecraft/network/protocol/common/custom/CustomPacketPayload.

What it needs from Kiln

• Mixin
• com.mojang.authlib.GameProfile
• net.fabricmc.fabric.api.client.networking.v1.ClientConfigurationConnectionEvents
• net.fabricmc.fabric.api.client.networking.v1.ClientConfigurationConnectionEvents.Start
• net.fabricmc.fabric.api.client.networking.v1.ClientConfigurationNetworking
• net.fabricmc.fabric.api.client.networking.v1.ClientConfigurationNetworking.ConfigurationPayloadHandler
• net.fabricmc.fabric.api.client.networking.v1.ClientConfigurationNetworking.Context
• net.fabricmc.fabric.api.networking.v1.PayloadTypeRegistry
• net.fabricmc.fabric.api.networking.v1.ServerConfigurationNetworking
• net.fabricmc.fabric.api.networking.v1.ServerConfigurationNetworking.ConfigurationPacketHandler
• net.fabricmc.fabric.api.networking.v1.ServerConfigurationNetworking.Context
• net.minecraft.network.FriendlyByteBuf
• net.minecraft.network.protocol.common.custom.CustomPacketPayload
• net.minecraft.network.protocol.common.custom.CustomPacketPayload.Type
• net.minecraft.network.protocol.common.custom.CustomPacketPayload.TypeAndCodec
• net.minecraft.server.network.ServerConfigurationPacketListenerImpl
• ServerPlayer.connection

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

Client side quality of life improvements on polymer powered servers!

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file polymer-qol-1.0.3+26.3.jar. The scan reads the mod's classes; it does not run them.