Whether to enable systemd in initrd. The unit options such as <a href="/nixpkgs/option/boot.initrd.systemd.services"><a href="/nixpkgs/option/boot.initrd.systemd.services" rel="nofollow">boot.initrd.systemd.services</a></a> are the same as their stage 2 counterparts such as <a href="/nixpkgs/option/boot.initrd.systemd.services"><a href="/nixpkgs/option/systemd.services" rel="nofollow">systemd.services</a></a>, except that <code>restartTriggers</code> and <code>reloadTriggers</code> are not supported.