Custom Data Directory

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Why Move the Data Directory?

By default, Polymerium stores everything under ~/.trident/:

• Settings and databases in ~/.trident/.polymerium/
• Shared cache in ~/.trident/cache/ (mod files, assets, Java runtimes)
• Your instances in ~/.trident/instances/

On Windows, ~ is typically C:\Users\<YourName>. If you have a small C: drive or want to keep game data on a separate SSD, the shared cache can grow large over time. Moving the entire data directory lets you reclaim that space.

How It Works

Polymerium uses a file called ~/.trident.home to override the default data location. This file:

• Lives at ~/.trident.home (your user profile directory)
• Contains a single line: an absolute path to the new data root
• Is read once at startup, before anything else

On Windows, ~/.trident.home is C:\Users\<YourName>\.trident.home.

Setting It Up

Step 1: Close Polymerium

Make sure Polymerium is not running. The override file is only read at startup.

Step 2: Choose a New Location

Pick an empty directory (or one that doesn't exist yet) on the drive you want to use. For example:

The directory will be created automatically on first launch.

Step 3: Create the Override File

Create a file named .trident.home in your user profile directory and put the absolute path in it:

Windows (PowerShell):

New-Item -Path "$env:USERPROFILE\.trident.home" -ItemType File -Force
Set-Content -Path "$env:USERPROFILE\.trident.home" -Value "D:\PolymeriumData"

Linux / macOS (Terminal):

echo "/mnt/games/polymerium" > ~/.trident.home

Step 4: Launch Polymerium

Start Polymerium. It will detect the .trident.home file, switch to the new data root, and create the necessary directories automatically.

Validation Rules

The path in .trident.home must:

• Be an absolute path (e.g. D:\Data, not ..\Data)
• Not point to an existing file (it can be a new directory, or an existing directory)

If the file exists but the path is invalid (relative path, or points to an existing file), Polymerium silently falls back to the default ~/.trident/.

On first launch with a new data root, Polymerium creates a fresh setup — settings revert to defaults and the shared cache starts empty. Old data in ~/.trident/ is not deleted or migrated automatically.

Migrating Existing Data

If you already have instances and settings under ~/.trident/ and want to move them:

1. Close Polymerium.
2. Create the .trident.home file pointing to the new path.
3. Copy the entire contents of ~/.trident/ to the new location.
4. Launch Polymerium — your instances, settings, and cache will be picked up.

Switching Back

To revert to the default location:

1. Close Polymerium.
2. Delete ~/.trident.home.
3. Launch Polymerium — it will use ~/.trident/ again.

Nothing is deleted when you switch or remove the override. Your data at the custom path remains as-is. Move it back manually if needed.

Use Cases

Limitations

• The .trident.home file is in your user profile directory — it applies globally, not per-instance.
• Polymerium does not migrate old data automatically. You must copy it yourself.
• The path must be absolute. Relative paths and environment variables are not supported.