The imake package contains the imake utility, plus a number of
support programs, such as mkdirhier, revpath, and xmkmf.

The X Window System used imake extensively up through the X11R6.9
release, for both full builds within the source tree and external
software.  X moved to GNU autoconf and automake for its build system
in 2005 for X11R7.0 and later releases, but still provides imake
for building existing external software programs that have not yet
converted, though they are not actively maintaining it for new OS
or platform releases.

Anyone shipping software still using imake to build should be
working on moving to something that is still adding support for
new platforms and runtimes.

Homepage:
https://xorg.freedesktop.org/
