I discovered a way of modifying Minix 3 the FreeBSD way.
Minix 3 has a stripped down version of Minix 3.1.1 which has only
"boot, drivers, include, kernel, servers, tools" in which FreeBSD's
"bin, sys/sys, sbin, usr.bin, usr.sbin, include, lib, libexec" can be copied and
and modified