This is a (slightly modified) copy of the official Docker Python example showing how slim can optimize the container image (making it more than 5 times smaller) using the example as-is without any advanced Docker tricks. The original image uses an already small slim(-buster) python base image as a starting point.

When you are done you'll have a couple of images like this:

REPOSITORY                                              TAG                 IMAGE ID            CREATED             SIZE
dslimexamples/server-python-flask-docker.slim       latest              ce9310bdf48b        21 seconds ago      24.2MB
dslimexamples/server-python-flask-docker            latest              e7765b45fb09        3 minutes ago       130MB

Use make (make build_and_slim) or the helper scripts directly (see the .command version for Mac OS if you like clicking :-)).

The _slim.env file declares the environment variables required by the slim helper scripts (in _slim). The helper scripts in _slim allow you to do everything you need with the app container (create/run/minify/etc). See _slim/README.md for more details.