Hey,
Mailman, the software that powers our mailing lists, is extremely old, by looking at https://lists.wikimedia.org/ you can guess how old it is.

I would really like to upgrade it to mailman 3 which has these benefits:
* Much better security (including but not limited to https://phabricator.wikimedia.org/T181803)
* Much better UI and UX
* Much easier moderation and maintaining mailing lists
* Ability to send mail from the web
* Ability to search in archives.
* Ability to like/dislike an email
* List admins will be able to delete emails, merge threads, and much more.
* Admins won't need to store passwords for each mailing list separately, they just login as their account everywhere.
* The current mailman stores everything as files (even mailing list settings), mailman3 actually uses a proper database for everything meaning proper backup and recovery, high availability and much more.

I have already put up a test setup and humbly ask you (specially list admins) to test it (and its admin interface), if you want to become a list admin, drop me a message. Keep in mind that we don't maintain the software so the most I can do is to change configuration and can't handle a feature request or solve a bug (you are more than welcome to file it against upstream though)

Here's the test setup:
* https://lists.wmcloud.org

Here's a mailing list:
* https://lists.wmcloud.org/postorius/lists/test.lists.wmcloud.org/

Here's an archive post:
* https://lists.wmcloud.org/hyperkitty/list/test@lists.wmcloud.org/thread/RMQPKSS4ID3WALFXAF636J2NGBVCN3UA/

Issues that I haven't figured out yet:
* This system has profile picture support but it's only gravatar which we can't enable due to our privacy policy but when you disable it, it shows empty squares and looks bad. Reported upstream [1] but also we can have a gravatar proxy in production. And in the worst case scenario we can just inject "$('.gravatar').remove();" and remove them. Feel free to chime in in the phabricator ticket in this regard: https://phabricator.wikimedia.org/T256541

* Upgrade will break archive links, making it work forever is not trivial (you need write apache rewrite rule) (You can read about it in https://docs.mailman3.org/en/latest/migration.html#other-considerations)

* Mailman allows us to upgrade mailing list by mailing list, that's good but we haven't found a way to keep the old version and the new ones in sync (archives, etc.). Maybe we migrate a mailing list and the archives for the old version will stop getting updated. Would that work for you? Feel free to chime in: https://phabricator.wikimedia.org/T256539

* We don't know what would be the size of the database after upgrade because these two versions are so inherently different, one idea was to check the size of a fully public mailing list, then move the files to the test setup, upgrade it to the new versionĀ  and check how it changes, then extrapolate the size of the final database. The discussion around the database is happening in https://phabricator.wikimedia.org/T256538

If you want to help in the upgrade (like puppetzining its configuration, etc.) just let me know and I add you to the project! It uses a stand-alone puppetmaster so you don't need to get your puppet patches merged to see its effects.

The main ticket about the upgrade: https://phabricator.wikimedia.org/T52864

[1] https://gitlab.com/mailman/hyperkitty/-/issues/303#note_365162201

Hope that'll be useful for you :)
--
Amir (he/him)