You will find a copy here of some files I downloaded from Keio's FTP mirror of Boudewijn Waijers' web site. These relate to the original UNIX NetHack: The Next Generation version 1.0 (written by Sebastian Klein), and the DOS port by Bill Foust. I gather Bill fixed a few bugs in the original code which is why I grabbed a copy.
You may know that Sebastian Klein asked Boudewijn Waijers to withdraw TNG from his website, which he did. Please, therefore don't bother Sebastian about TNG. He has obviously moved on. For the lawyers out there, here is an extract from Sebastian's documentation...
6. The Legal stuff
I, being of sound mind and body, do write down on this day of
the twentieth of May in the year nineteenhundredninetyfour,
for all to see, that these patches of Nethack shall be placed
in the Public Domain and therefore free to use for anybody
without any restriction. However, I disclaim any liability
for any damage or consequences caused by these patches or
bugs in them. By using this software you agree to be
bound by these terms.
However, note that in the act of applying my patches to
the actual NetHack sources causes the resulting program
to be completely bound to the NetHack license agreement
as stored in dat/license.
You should note that these are both based on NetHack version 3.1.3. One day I may port these to version 3.3.
Sebastian Klein's original UNIX version:
Bill Foust's DOS port: