The images we provide on Dockerhub are different than those on NGC.
We have no plans to publish the Dockerfiles used to build NGC images - they would be of limited utility outside NVIDIA since they reference internal package repositories that could not be accessed from outside.
To modify the NGC images, NVIDIA recommends building on top of them (using the FROM directive in your Dockerfile) rather than rebuilding from scratch; there are example derivative Dockerfiles inside each image in the /workspace/docker-examples directory. This not only avoids a full rebuild but it also allows customizations to be now easily carried forward from one month’s release to the next.
Thanks for your interest in NGC!