[johnlorentzson]

DOOM was definitely made with DOS in mind, but it also ran on NeXT from the beginning. It's pretty portable actually. Since you cited Fabien Sanglard, I guess I should mention that his book about DOOM's source code (Game Engine Black Book: DOOM) explains how the portability stuff (as well as almost everything else) worked in great detail.

[macintux]

Several of us would regularly play it in a Chemistry computer lab on SGI workstations. Annoyed the hell out of the students doing molecular simulations, regrettably.