Technically speaking is written in C++, in practice is really written in C and compiled with a C++ compiler.
As for testing, of course I will need help on that: it is working for me on 10.3 and 11.0 as well as on Linux (at least on those Linux distros that provide libudev), but basically it was tested against USB sticks only.
SD card readers support need to be included, and that's the area that would greatly benefit from additional feedback, because there are a range of device available out there, some works on top of USB stack, other are PCI devices, thus different drivers and different device names.
Then there is another aspect to carefully evaluate: USB devices are really user accessible in GhostBSD, due to some rules added to devd.conf, but not on Linux and I didn't checked about pure FreeBSD so far.
I will publish the code on my github account very soon (few days).
at least once I published a link about the tool on #ghostbsd .... most likely you missed it. Your fault !
my "minimal ISO" was small, but I was unable to make it fit a CD size, ~900 MB is what I was able to achieve, but sure, we will try again.