Ok, it turns out Debian does not run on Intel quark processors, see https://www.debian.org/releases/jessie/i386/ch02s01.html.en .
And this is the processor iot2000 devices use.
Sorry this took some time 
I’ve pinged our team to remove the Debian base images for iot2000.
You can use Alpine base images instead (I’ve tested one, it works) but you’ll need to adapt your Dockerfile (replace apt-get with apk, etc…).