DarkMatter is a new source port for QUAKE III: ARENA, based on Quake3e (https://github.com/ec-/Quake3e). It is part of an ambitious project to ultimately bring the gameplay experiences of older QUAKE® titles together into one feature-rich package. See https://github.com/themuffinator/dm-game for the game logic development.
Why do you think that https://github.com/yquake2/yquake2 is a good alternative to dm-engine