I have a Dockerfile with a sequence of RUN instructions that execute \"apt-get install\"s; for example, a couple of lines:
RUN apt-get install -y tree
RUN apt-ge
Have a look at :
https://github.com/GoogleCloudPlatform/container-diff
This tool can diff local or remote docker images and can do so without requiring docker to be installed. It has file as well as package level "differs" (for example: apt, npm, and pip) so that you can more easily see the differences in packages that have changed between two docker images.
Disclaimer: I am a contributor to this project