DF - https://daringfireball.net/

Dfly - http://www.dragonflydigest.com/

E

HN - https://news.ycombinator.com/

K - https://kottke.org/

L - https://lobste.rs/

ML

MR - https://marginalrevolution.com/

R - probably https://old.reddit.com/r/netsec/

SOS

SSC

ars - https://arstechnica.com/

bsdnow

cox - https://twitter.com/josephfcox

danluu - https://twitter.com/danluu

green - https://twitter.com/matthew_d_green

grugq - https://twitter.com/thegrugq

jwz

solar - https://twitter.com/solardiz

trivium - http://leahneukirchen.org/trivium/

vermaden - https://vermaden.wordpress.com/

white - https://twitter.com/kennwhite