DNS Implementations

Authoritative Server

• BIND named https://www.isc.org/downloads/bind/
• NSD https://www.nlnetlabs.nl/projects/nsd/about/
• Knot DNS https://www.knot-dns.cz/
• PowerDNS Authoritative Server https://www.powerdns.com/auth.html
• MaraDNS https://maradns.samiam.org/
• YADIFA https://www.yadifa.eu/
• Delphinusdnsd https://delphinusdns.org/

Recursive Caching Server

• BIND named https://www.isc.org/downloads/bind/
• Unbound https://www.nlnetlabs.nl/projects/unbound/about/
• PowerDNS Recursor https://www.powerdns.com/recursor.html
• Knot Resolver https://www.knot-resolver.cz/
• MaraDNS Deadwood recursive caching resolver https://maradns.samiam.org/

Simple Forwarder

• OpenBSD rebound http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/rebound/

Lookup Tools

• BIND Delv https://www.isc.org/downloads/bind/
• BIND DiG https://www.isc.org/downloads/bind/
• Drill https://www.nlnetlabs.nl/projects/ldns/about/

Development API Functions

• BSD Resolver Library http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/resolv/
• wdns low-level DNS library https://github.com/farsightsec/wdns
• djb dns library https://cr.yp.to/djbdns/blurb/library.html
• DNS library in Go https://github.com/miekg/dns
• BIND 10 / Bundy libdns++ https://github.com/bundy-dns/bundy/tree/master/src/lib/dns
• dns.c http://www.25thandclement.com/~william/projects/dns.c.html
• UDNS http://www.corpit.ru/mjt/udns.html
• getdns https://getdnsapi.net/
• LDNS https://www.nlnetlabs.nl/projects/ldns/about/
• dnspython http://www.dnspython.org/