A CIA build is now available here :)
The thread at https://bbs.nextthing.co/t/port-of-numptyphysics-to-pocket-c-h-i-p/12358 now includes a guide which commands are needed.
Is there an easy way to do a CIA build via devkitPro? And is there an easy way to test the CIA on a device? By default the SDK spits out 3dsx files, so that's as far as I got up to now :)