After answering where to get and how to build the k-drive, TinyX a few tines on the xorg mailing list I figured it is about the tine to let Google now about it more verbosely:
Keith Packard’s k-drive based, TinyX was merged into the mainline xorg-server package, so it is as easy as downloading the latest, greatest X.org release and configure the xorg-server package with something like:
--enable-kdrive --disable-dri --disable-xorg --disable-xorgcfg
along with the other options like –prefix et al. as appropriate.
If you want all this in an automated way, with cross compile support you can also take a look into the T2 SDE Project which among others supports exactly this: Cross compiling X.org, including the tinier k-drive variant, even with alternative C libraries such as uClibC and dietllibC. To check it out and give it a try the T2 Rescue target provides tiny ISO images, pre-built for at least x86 and x86-64 (other like powerpc and sparc are easily buildable from the T2 source as well).