Modpack Development with Git

Use Git to version-control your modpack — track changes, collaborate, and publish releases.

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Why Git?

A Polymerium instance is already Git-friendly by design:

profile.json is the modpack definition — plain JSON, diffable
import/ contains the distributable files — configs, resources, custom content
build/ is the Run Directory; it can contain personal data, so keep it out of Git and back it up separately when needed. persist/ is Local Data and should stay private.

This means you can put an instance under Git and get meaningful diffs, branching, and collaboration.

Setting Up

Initialize a Git repo in the instance directory:

cd instances/my-modpack
git init

Create a .gitignore:

build/
persist/
data.lock.json

Commit the initial state:

git add profile.json import/
git commit -m "Initial modpack"

What to Track

File	Track?	Why
`profile.json`	✅	The modpack definition — version, loader, mod list
`import/`	✅	Distributable files (configs, resources)
Imported native patches (`patches/data.patch.json`, `patches/import/`)	✅ If used	Launch declarations that travel with a Trident modpack
`build/`	❌	Runtime output; may contain saves and other data not backed up elsewhere
`persist/`	❌	Player data (saves, screenshots)
`data.lock.json`	❌	Deploy cache, auto-generated

On the instance home page, the development overview widget summarizes Git status, Pack Source files, unsynced working-copy changes, patches, release attachments, and the last run. Its compact view hides categories with nothing to report. Open Workspace to review individual file changes.

Iterating on Configs

Launch the game and modify settings in-game.
Changes land in build/.
Open the Workspace to review diffs.
Sync confirmed changes to import/.
Commit:

git add import/
git commit -m "Tweak performance configs"

Adding / Removing Mods

Add or remove mods in Polymerium's Setup tab.
profile.json is updated automatically.
Commit:

git add profile.json
git commit -m "Add Sodium and Lithium"

Switching Branches

You can use Git branches for experimental modpack versions:

git checkout -b experiment/new-loader
# Change loader in Polymerium, add/remove mods
git add profile.json import/
git commit -m "Switch to NeoForge"
# Test...
git checkout main  # Go back to stable

Collaboration

Push the repo to a shared remote (GitHub, GitLab, etc.).
Co-authors clone the repo into their instances/ directory.
Each person's build/ and persist/ are local and untracked.
Collaborate on profile.json and import/ via normal Git workflows.

Publishing a Release

Tag a release:

git tag v1.2.0
git push origin v1.2.0

Export the instance using Polymerium's export feature.
Upload the exported modpack to CurseForge, Modrinth, or both.

Automating Exports with the CLI

You can skip the GUI and export from the command line using Trident CLI:

trident instance export my-modpack --format modrinth --output ./releases/

This works well in CI/CD pipelines. For example, trigger an automatic build and export whenever you push a tag:

# .github/workflows/release.yml (simplified)
on:
  push:
    tags: ['v*']
steps:
  - uses: actions/checkout@v4
  - run: trident instance export my-modpack --format modrinth --output ./releases/
  - # upload ./releases/* to Modrinth / CurseForge

See the headless server guide for a full CI/CD example.

Tips

Close Polymerium before Git operations — Polymerium may be watching profile.json for changes. Quit, do your Git work, then reopen.
Don't edit profile.json manually for version changes — it's safer to create a new instance and migrate packages.
Use the workspace as your staging area — it's purpose-built for promoting in-game changes from build/ into import/.