rimpack

rimpack is a Python CLI for building, validating, and launching RimWorld modpacks from human-authored project files.

It treats a modpack as a normal project directory:

• pack.toml is the root manifest.
• mods/*.list files define authored mod intent.
• rules/ contains optional activation and ordering rules.
• generated/ contains outputs that can be regenerated.
• launch state stays machine-local instead of mutating the real RimWorld install.

The repository is spec-driven. The authoritative behavior and file-format definitions live in specs/.

Current Capabilities

Today, rimpack can:

• initialize a new modpack project with rimpack init
• inspect RimWorld mods with rimpack load-mods
• resolve Steam Workshop items with rimpack resolve steam
• copy a Workshop mod into the current pack's local/mods with rimpack localize
• subscribe and unsubscribe Workshop mods
• add mod references to a declared .list file with rimpack add
• append ordering rules with rimpack add-ordering-rule
• validate a modpack before launch with rimpack validate
• launch a modpack through a symlinked runtime tree with rimpack launch

Activation rule files are supported by the project format and validation pipeline, but there is not yet a dedicated CLI command to author them.

Install

The project uses Python 3.12+ and uv.

uv sync --dev
uv run rimpack --help

You can also run the console script directly after syncing:

rimpack --help

First Run

Running rimpack with no command creates a user-local config file if one does not already exist. That config stores absolute machine-local paths such as:

• the RimWorld install directory
• the Steam Workshop content directory for app 294100

You can also provide them through environment variables:

• RIMWORLD_FOLDER
• STEAM_WORKSHOP_FOLDER

Quick Start

Initialize a new pack:

uv run rimpack init .\MyPack

Add a Workshop mod to the @libraries list:

uv run rimpack add @libraries steam:2009463077

Copy a Workshop mod into the current pack's local/mods directory:

uv run rimpack localize steam:2009463077

Validate the pack:

uv run rimpack validate

Leave temporarily resolved Workshop mods subscribed after validation:

uv run rimpack validate --no-clean

Launch it:

uv run rimpack launch

Documentation

Browsable project documentation lives in docs/:

• docs/index.md
• docs/getting-started.md
• docs/cli.md
• docs/modpack-format.md
• docs/configuration.md

A GitHub Actions workflow publishes those docs to GitHub Pages on pushes to main.

Development

The expected local checks are:

uv run ruff check .
uv run basedpyright
uv run pytest