Thank you for your interest in contributing to Millennium Dawn! This file is a pointer to the team docs. The full guides live on the documentation site.
| Guide | What it covers |
|---|---|
| Developer Setup Guide | Prerequisites, cloning, pre-commit hooks, dev tools, VSCode, day-to-day workflow. Start here. |
| Contributing Guide (Docs Site) | Docs site setup, bun run dev, content conventions, link rules, the docs CI pipeline. |
| Code Stylization Guide | Formatting and code structure for HOI4 script files. |
| Content Review Guide | Quality checklist and developer expectations. |
| Focus Tree Design Principles | Branch structure, pacing, choices. |
| Git Workflow | Fork workflow, branch naming, commits, PRs. |
| AI Modding Guide | Setting up local AI models for development. |
python3 tools/dev_setup.py # install hooks and Python tool dependencies
python3 tools/dev_setup.py --check # verify environment
python3 tools/dev_setup.py --docs # also install Node.js + Bun for docs site workSee the Developer Setup Guide for the full walkthrough.
| Area | Examples |
|---|---|
| Focus Trees | New trees, branch reworks, prerequisite fixes |
| Events & Decisions | Event chains, decision categories, triggered events |
| Ideas & National Spirits | New ideas, modifier tuning, icon assignments |
| AI & Balance | Strategy plans, equipment variants, stat tweaks |
| Localisation | English string fixes, tooltip accuracy |
| Graphics | Portraits, focus icons, event pictures, 3D models |
| Map & History | State boundaries, country history, OOBs |
| Documentation | Docs site content, guides, tutorials, dev diaries |
| Tooling | Python scripts, CI improvements, pre-commit hooks |
| Bug Fixes | Crash fixes, trigger errors, typos |
Non-English localisation is managed through Paratranz. Do not submit translations directly.
AI tooling is welcome. The full policy is on the Developer Setup Guide. The short version:
- Code: AI may draft, refactor, or debug. Review all output line-by-line. Run pre-commit. Verify game objects exist. Do not submit raw AI output.
- Localisation: AI may draft English strings. Human review required. Non-English is Paratranz-only.
- We highly discourage pure AI generated localization and writing as it does not add anything meaningful to the description and takes away from part of the fun of modding.
- Graphics: Pure AI-generated art is not allowed. AI-generated military vehicle side profiles are acceptable only when no existing profile is available, and must be manually finalized and reviewed.
- Docs/PRs: AI may draft. Review for accuracy. Do not add "Generated with" footers or co-author trailers.
- All reported issues (including those generated by AI) must follow all standards and conventions as provided by the Millennium Dawn Mod team.
- Accountability: Any code that the AI generates, you own, so you are responsible for any issues that may arise from the utilization of this technology.
- Keep PRs focused on a single feature or fix when possible.
- Pull Request descriptions need to be straightforward and to the point. Do not waffle about the why or how. We need to know what was broken and what the fix is.
- Update Changelog.txt under the current top-most version heading (see Changelog Guidelines).
- Add yourself to AUTHORS.md if this is your first contribution.
- CI validation must pass and a team leader must approve before merge.
- CI validation includes all validation and linters that exist within the framework under the Coding Standards and Validations.
- PRs that only reformat or restructure existing code without a functional reason.
- Machine-translated localisation (we utilize Paratranz for our translation projects.)
- Content that violates Paradox Interactive's Terms of Service.
- Large, unfocused PRs that touch many unrelated files. Break them up.
- Code that is from other mods without documented consent from the other mod teams.
- Graphics that are copyrighted without proper documented consent form their owners.
- Documentation Site — all guides, tutorials, and reference docs
- Discord — team communication
- tools/README.md — dev tools directory layout
For questions, join the Discord or open an issue on our GitHub issue tracker.