Hello David, There is an upcoming feature in Docker which allows building containers the way you described. It's called multi-stage builds: https://docs.docker.com/engine/userguide/eng-image/multistage-build/
It's available in beta versions only for now. Btw, I'm using https://www.notion.so/ for taking notes while I'm researching or developing something. It's like a wiki but real-time collaborative and allows publicly sharing your results. I highly recommend you copy paste your commands into such a tool OR at least into a text file as you are developing something, then it's a lot easier later to turn it into an actual article / blog post / wikipage. As a middle ground between Notion and a plain text file is creating a markdown file which you can store on Dropbox, Google Drive, GitLab, GitHub for later sharing. The secret to create a Markdown file effortlessly is to use the cross-platform https://typora.io/ editor, because it is NOT a dual-pane editor. It actually shows you the content you typed in a nicely rendered format, EXCEPT around your cursor, where it reveals the underlying markdown characters and allows direct, plain text interaction with them. I know these sound nuances, but such details can really affect our psyche and make the difference between creating and liberating knowledge or indefinitely procrastinating over it. -- tom
