---
title: Overview
description: 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](/docs/getting-started/installation) guide — you'll be playing in minutes.
- **Coming from another launcher?** Check the [Migration Guide](/docs/guides/migrate-from-other-launchers) for a quick transition.
- **Curious how it works?** Read [Core Concepts](/docs/concepts/metadata-driven) to understand what makes Polymerium different.

## What You'll Find Here

| Section | What It Covers |
|---------|---------------|
| [Getting Started](/docs/getting-started/installation) | Download, install, create an instance, add mods, play. |
| [Core Concepts](/docs/concepts/metadata-driven) | The ideas behind Polymerium: metadata-driven instances, four-layer directories, deploy pipeline. |
| [Managing Instances](/docs/managing/accounts) | Accounts, import/export, snapshots, tags, Java management, settings. |
| [Advanced](/docs/advanced/rules) | Deployment rules, workspace, modpack development, CLI, MCP/AI agent mode. |
| [Guides](/docs/guides/migrate-from-other-launchers) | Step-by-step walkthroughs for specific tasks — no theory, just doing. |
