Home page for the entire suite (in French) with some screenshots: https://lasuite.numerique.gouv.fr/
Code bases are on GitHub and they use English there: https://github.com/suitenumerique/
Dev handbook (in English): https://suitenumerique.gitbook.io/handbook
Not French and I can't say I personally tried deploying any of them, but I've been admiring their efforts from afar for a while now.
For open source code, there is no risk of confidential information being given to the US government (since there is no confidential information), and moving to another forge would be pretty simple if necessary.