Building turris os with modem manager

Hi, would anybody be able to help out with knowledge on how I can build turris os with modem manager?

Somehow I don’t understand what you mean by the term “modem manager”.

Its a method of controlling cellular modems supporting all the major communication protocols QMI, MBIM etc, previously ported and maintained by Aleksander Morgado https://sigquit.wordpress.com/tag/libqmi/ for building into most linux systems.
It is now looked after by openwrt, https://openwrt.org/docs/guide-user/network/wan/wwan/modemmanager#modemmanager

I have built firmware with this package before but the build system for Turris has some extra complexities that I’ve not yet figured out such that i can build modemmanager into a firmware build.
I guess the only solution is to go to openwrt firmware on my omnia, but i thought as Turris OS is an openwrt fork there would be a way to build this package for the omnia.

Package modemmanager was just a month ago merged into the master branch of OpenWrt packages repository. It was not cherry-picked into openwrt-19.07 branch, so it means that it won’t be included in not released OpenWrt 19.07. There’s still an opinion to use uqmi and umbim.

If you would like to compile modemmanager, you need to have OpenWrt 18.06 (Turris OS 4.0) or not-released-yet OpenWrt 19.07 (Turris OS 5.0) on your router and then start with the documentation for turris-build repository. Of course, there’s a possibility to try master branches of all repositories (inc. feeds) on your router, but it is not supported and for more details take a look at switch-branch command, which is on your router.

Thanks for the info, i will attempt to build some firmware.