1. Install Fabric Loader
Download the Fabric installer, choose Minecraft 26.3 and install Fabric Loader.
Install
How to install Firmament on Fabric 26.3
Installing Firmament takes about five minutes. Follow the steps below, or grab the build first from the download page.
2. Add the prerequisites
Install Fabric Loader, Fabric API and Fabric Language Kotlin into your mods folder.
3. Add Firmament
Place Firmament-26.3.jar into your .minecraft/mods folder.
4. Launch the game
Start Minecraft with the Fabric 26.3 profile.
5. Open the menu
Press /firm config in game to open Firmament and toggle the modules you want.
After installing
Open the menu and configure
Press /firm config in game to open Firmament, then browse the full module list. If you play on Hypixel SkyBlock, keep the client-side build up to date for the best results.