We’ve tracked down the issue affecting nvidia.runtime.
It’s a bug in how we generate lxc.environment.
Once we have this merged, we’ll be cherry-picking that fix to the Zabbly packages.
@Foxboron on the Arch Linux side helped track this down earlier today, so I expect Arch will also get a cherry-pick in pretty short order 
@adamcstephens you’ll likely want to do this in Nix as well.