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Terraforming Mars Open-source

This is an open-source online implementation of the great board game Terraforming mars. It is not affiliated with FryxGames, Asmodee Digital or Steam in any way.

Note: This project has no affiliation with "Rebalanced Mars", whose authors have refused to open-source their code. We believe this is both a violation of our GPL3 license, and also of the spirit of collaboration that this project tries to foster. Note that any new features you see on this repo made available on that server are without our permission.

Buy The Board Game

The board game is great and this repository highly recommends purchasing it for personal use.

⬤ I want to join the community!

Join us over on Discord!.

⬤ I want to play!

There's a instance available at It's generally reliable, but read more below.

There's also this excellent YouTube playlist focused on tutorials custom for this app.

NOTE: This site is restarted daily. A multiplayer game will remain available for 15 days, after which it will be flushed from the database. Unfinished solo games are flushed after one day. We continue to make stability and scalability improvements in step with growth and popularity, but to make sure your game remains, we highly recommended to host your own web server.

⬤ I want to learn how to play

There are far too many good tutorials online. Here are the rulebooks, though.

⬤ I want to run a copy of the server locally

Check out our Local setup wiki page

Honestly, it's really simple.

⬤ I want to run a copy of the server on Heroku

Check out our Heroku setup wiki page

(As of 2022-11-28, Heroku no longer has a free tier. However, it is still our recommended way to deploy, as they're the clearest instructions.)

⬤ I want to run a copy of the server on Docker

Check out our Docker setup wiki page

⬤ I want to report a bug or feature request

Add it to our issues tab.

⬤ I want to contribute to development

See contribution guide and local development setup.

⬤ I want to win!

Me too, pal. Me too.


Thanks goes to these wonderful people:

Brian Folts: All the things
Vincent Moreau: Venus, Prelude, Hellas & Elysium, Colonies, Turmoil
alrusdi: Front End, internationalization
Simeon Simeonov: UX, cards and Colonies design
Pierre Hilbert: Turmoil and helps with the things
nwai90: Community and Political Agendas fan-made expansions, and helps with the things
Pocc: He did that one thing one time
Robert Konigsberg: Ares fan expansion, The Moon fan expansion, infrastructure cleanup, code reviews, two opinions too many.
chosta: Front end and back end

Lynesth: Help with the things

푸른이(derornos): 한국어화 옮긴이(Korean translator)
메일(email): / 카카오톡(KakaoTalk, Messenger): link