My gut tells me the problem has to do with node.js and npm. I was following a quick start guide from metal.js. There are very little resources online.
Here is the link: http://metaljs.com/docs/
In the terminal, I was able to navigate to the folder to 1. Hello World and create its npm dependencies, by typing: sudo npm i, but I could not build the demos/index.html file by typing npm run build in the same directory.
I have the latest install on node.js and npm. I am using a mac and for metal.js I am using boilerplated with JSX provided.
Thanks in advance!