Flarum
Homepage: https://flarum.org/
Flarum is a delightfully simple discussion platform for your website. It's fast, free, and easy to use, with all the features you need to run a successful community. It's also extremely extensible, allowing for ultimate customizability.
Usage
Set flarum_enabled: true in your inventories/<your_inventory>/group_vars/nas.yml file.
Flarum web interface can be found at http://ansible_nas_host_or_ip:8001. Login with default credentials (flarum/flarum) and change them.
Specific Configuration
Enable flarum_plugins_enabled to automatically install a set of useful Flarum extensions.