Polymerium

Overview

Learn how to use Polymerium — from your first instance to advanced modpack development.

Polymerium is a cross-platform, open-source Minecraft launcher built around a simple idea:

Your instance is a recipe, not a pile of file copies.

Instead of duplicating mod files for every instance, Polymerium stores each file once and builds instances on demand. The result: less disk usage, instant switching, and a workflow that actually makes sense for modpack development.

Where to Start

  • New to Polymerium? Follow the Getting Started guide — you'll be playing in minutes.
  • Coming from another launcher? Check the Migration Guide for a quick transition.
  • Curious how it works? Read Core Concepts to understand what makes Polymerium different.

What You'll Find Here

SectionWhat It Covers
Getting StartedDownload, install, create an instance, add mods, play.
Core ConceptsThe ideas behind Polymerium: metadata-driven instances, four-layer directories, deploy pipeline.
Managing InstancesAccounts, import/export, snapshots, tags, Java management, settings.
AdvancedDeployment rules, workspace, modpack development, CLI, MCP/AI agent mode.
GuidesStep-by-step walkthroughs for specific tasks — no theory, just doing.

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