gdnsd is an Authoritative-only DNS server.

The initial g stands for Geographic, as gdnsd offers a plugin system for
geographic (or other sorts of) balancing, redirection, and
service-state-conscious failover. If you don't care about that feature,
it's still quite good at being a very fast, lean, and resilient
authoritative-only server for static DNS data.

gdnsd is written in C using libev and pthreads with a focus on high
performance, low latency service. It does not offer any form of caching or
recursive service, and does not support DNSSEC.

WWW: https://github.com/blblack/gdnsd/