ModemManager is the default mobile broadband management system in most Free and Open Source Software systems, including not only standard distributions like Debian, Ubuntu, Fedora or Arch Linux , but also in mobile devices running postmarketOS, PureOS or Mobian.

Basic 5G support is already available in current versions of ModemManager, although there are key differences with earlier technologies like 3G or 4G that should be considered, e.g. with respect to network attach settings or multiple/concurrent access technology support.

Advanced 5G features, like 5G network slicing support, are not yet supported in ModemManager. These are in the roadmap for future releases, and open for discussion with the community on how to best implement them.

This talk covers past, present and future of the 5G technology support in ModemManager. How we have reached its current state, what technical debt we carry, and how the future implementation may look like.