The nested-instance host that used to live here (the scheduler, the guest-state
snapshot and the reentrant loaders, built into doom_ace through MTX_DIR) is now part
of Kodoque1/doom_ace, in its
nested/ directory, with this
repository's history merged in. engine/makefile builds it from there by default, so
one clone of doom_ace is all you need.
That repository is also where Doomception lives: three Doom instances running inside one DOOM2.EXE, the article about how it works, and a challenge to write the switch yourself.
This repository is kept, archived, so that old links still lead somewhere.