Steve Huffman’s Reddit username is spez. He has used the account publicly for years, and the name is closely associated with his role as Reddit’s co-founder and chief executive officer.
Huffman launched Reddit in June 2005 with his University of Virginia roommate Alexis Ohanian. The pair developed the original idea through Y Combinator’s first class, with Huffman programming the initial website in Lisp. As Reddit grew, the founders sold it to Condé Nast in October 2006.
Huffman left Reddit in 2009, later co-founding the travel search website Hipmunk. He returned to Reddit as CEO in July 2015. Because he continued to participate on the platform through the username u/spez, Reddit users commonly refer to him simply as “Spez.”
The other options are connected to Reddit’s history but do not identify Huffman. Yishan Wong was a later Reddit CEO, Aaron Swartz was an early co-owner and contributor, and “kn0thing” is Alexis Ohanian’s well-known Reddit username. Thus, “spez” is the single canonical answer.