PolyLib is a compact Minecraft library mod offering helper classes for mod development, including easier GUI creation. It supports Forge, NeoForge and Fabric for Minecraft 1.18–26.3. Its source code is available on GitHub, and Architectury is no longer required from Minecraft 26.1.2 onward.
Rent your own Minecraft server and install PolyLib with one click from the panel when your chosen mods need this library.