Series 550 freezes laptop

The nvidia-open-dkms solved for me the random freezes and the system runs stable with them now. But I cannot uses suspend with them. X11 doesn’t come up again. When I try to reboot, systemd says that nvidia-suspence is blocking that.
I am using NixOS, not Arch (because it seems like everyone else in here uses Arch or an Arch-based distro).