So I just learned about the
.dockerignore file after realising how uploading my
context to the docker deamon got 1.5 GB big and took forever.
Look at the ref docs here: https://docs.docker.com/engine/reference/builder/#dockerignore-file
But the kicker was to find out how to use it as a whitelist and ignore everything but the stuff u need docker to put in your container:
# Ignore everything * # only add prebuild binary !bin/linux/*
This turns out to be a lifesaver bin node/rust projects where the working directory contains a giant pile of generated/compiled junk!