[feld]

What are they? I've certainly never heard of them or used them. Are they used in production or are they toys?

DHCP: isc-dhcp or dnsmasq

DNS recursor: dnsmasq, unbound, bind, djb's dnscache, maradns

None of these are written in memory safe languages, but they're the only ones I would trust because they have YEARS of testing and getting the RFCs right.