OBS Studio

OBS Studio is free and open source software for video recording and live streaming, licensed under the GNU GPLv2 license.

Using the Virtual Camera

The virtual camera requires the v4l2loopback kernel module to be installed, like so:

{ config, ... }:
{
  boot.extraModulePackages = with config.boot.kernelPackages; [
    v4l2loopback
  ];
}