Hack is somewhat the missing link between Rogue and NetHack, and it has always got less attention than these two. It seems that its history is a lot more complicated than I thought.
The first Hack was written by Jay Fenlason in 1982, with help from Kenny Woodland, Mike Thome and Jon Payne. It was a clone of Rogue, but with a lot more monsters, and distributed under the BSD license. It seems that this was only ever a Unix program, and that it has been lost.
In 1984, Andries Brouwer posted a Hack 1.0 to net.sources. He developed it up to 1.03, it was distributed under a copyright notice of the Stichting Mathematisch Centrum, Amsterdam.
In 1985, Michiel Huisjes posted a Hack for PDP-11 to net.sources in five messages (1, 2, 3, 4, 5). Apparently this version first introduced pets, in the form of a little dog.
Then there is a sourceless anonymous PC executable known as Hack121, since it is found in an archive with the name hack121.zip. It starts out in a shop where the player can buy equipment, uses the extended IBM character set and colors.
What I don’t know is how and if all these versions relate to Don Kneller’s Hack, which dates back to 1985 and which I had always assumed to be the basis for NetHack. In the doc to his Hack 1.0.3, no other Hack is mentioned, only Rogue.
As a final note, the origin of the name
Hack seems unclear too. I had always understood it to be derived from the fact that Rogue had been hacked. But it may also be derived from a lesser known usage of hack at MIT (New Hacker’s Dictionary):
To explore the basements, roof ledges, and steam tunnels of a large, institutional building, to the dismay of Physical Plant workers and (since this is usually performed at educational institutions) the Campus Police. This activity has been found to be eerily similar to playing adventure games such as Dungeons and Dragons and Zork.
Note: Shortly after posting this, I noted a few inaccuracies. They are corrected in the next entry.