Fuck Docker, in general.
- Access the host from within the container using 172.17.0.1.
- On Windows and OS X, this is automatically aliased to host.docker.internal.
Flattening an image
You can't flatten an image, so far as I know, but you can flatten a container into an image:
docker export CID > flatten.tar
docker import - INAME < flatten.tar
(FIXME can you pipe one into the other, eliminating the middleman?)