GXemul is an experimental instruction-level machine emulator. Several
emulation modes are available. In some modes, processors and surrounding
hardware components are emulated well enough to let unmodified operating
systems (e.g. NetBSD) run as if they were running on a real machine.

The emulator is written in C, does not depend on third-party libraries,
and should compile and run on most 64-bit and 32-bit Unix-like systems,
with few or no modifications.

Devices and processors are not simulated with 100% accuracy. They are
only "faked" well enough to allow guest operating systems to run without
complaining too much. Still, the emulator could be of interest for
academic research and experiments, such as when learning how to write
operating system code.