Should be straightforward, as rALK provides the service in support/freebsd/rc.d/alkane
Not sure if we want to submit it upstream or keep it internal. In the second case, we don't have any FreeBSD tree for Nasqueron software.
Version for FreeBSD 13 is published at https://packages.nasqueron.org/freebsd/FreeBSD%3A13%3Aamd64/