Hi again @asibbald,
I just tried to run the Phoenix server using the code in the stateless_components directory and was able to compile and run the server without issue. Looking more closely at the error message you reported, this is the part that is important:
** (EEx.SyntaxError) /Users/alister/Programming/Practice/elixir/liveview/code/stateless_components/pento/lib/pento_web/live/product_live/show.html.leex:43:1: missing token ‘%>’
Looks like there is a syntax error on line 43 of stateless_components/pento/lib/pento_web/live/product_live/show.html.leex. Is it possible that you edited that line by mistake and accidentally eliminated a %> tag? I would start by checking that. If you’re still stuck and you want to push up your code to a repo to share with me, I’d be happy to take a look.