OBS Virtual Camera

Getting the OBS Virtual Camera is a bit more complex that it should be but oh well.

In configuration.nix:

boot = {
    extraModulePackages = with config.boot.kernelPackages; [ v4l2loopback ];
    extraModprobeConfig = ''
      options v4l2loopback devices=1 video_nr=1 card_label="OBS Cam" exclusive_caps=1
    '';
};

Then just add OBS to your packages list or use home-manager's OBS program options.