Dan bernstein wrote Qmail, DJBDNS and Cryptography algorithms

https://en.m.wikipedia.org/wiki/Bernstein_v._United_States

Qmail https://en.m.wikipedia.org/wiki/Qmail

Djbdns https://en.m.wikipedia.org/wiki/Djbdns

https://en.m.wikipedia.org/wiki/Daniel_J._Bernstein