Whenever I give a presentation, write a blog post, or make a video, I like to run all of my examples and demos locally and on an Oracle Cloud instance. I keep a Virtual Box machine or a Docker container ready on my laptop just in case I can't get to the internet, but for speed and dependability, you just can't beat a cloud instance.
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I like to have some automation scripts handy to create and destroy my environments, and depending on what I'm doing, that can sometimes take a while.