Izchak Miller was a Professor of Philosophy who taught at MIT and Stanford, amongst other places, and was employed at Xerox PARC for a while. Izchak joined the DevTeam in 1986, at which time he was working at the University of Pennsylvania. He was, in fact, one of the founding members of the DevTeam, and was instrumental in synchronizing and arbitrating the team for a long time, up until the release of version 3.1.3. He personally wrote much of the shopkeeper code, as well as major contributions to prayer, alignments, and the version 3.1 rewrite of Gehennom.
Izchak died on the 1st of April 1994 from complications due to cancer, at the age of 58. The DevTeam dedicated NetHack 3.2 in his memory and added a shopkeeper named Izchak. It is considered very poor form to mistreat this particular shopkeeper, despite the extent to which his co-workers are maligned by everyone.
Encyclopaedia entry
The shopkeeper of the lighting shop in the town level of the
gnomish mines is a tribute to Izchak Miller, a founding member
of the NetHack development team and a personal friend of a large
number of us. Izchak contributed greatly to the game, coding a
large amount of the shopkeep logic (hence the nature of the tribute)
as well as a good part of the alignment system, the prayer code and
the rewrite of "hell" in the 3.1 release. Izchak was a professor
of Philosophy, who taught at many respected institutions, including
MIT and Stanford, and who also worked, for a period of time, at
Xerox PARC. Izchak was the first "librarian" of the NetHack project,
and was a founding member of the DevTeam, joining in 1986 while he
was working at the University of Pennsylvania (hence our former
mailing list address). Until the 3.1.3 release, Izchak carefully
kept all of the code synchronized and arbitrated disputes between
members of the development teams. Izchak Miller passed away at the
age of 58, in the early morning hours of April 1, 1994 from
complications due to cancer. We then dedicated NetHack 3.2 in his
memory.
[ Mike Stephenson, for the NetHack DevTeam ]