The stretch goal refers to live_patch/2 along with a url to the document of this:
http://hexdocs.pm/phoenix_live_view/Phoenix.LiveView.Helpers.html#live_patch/2
However on clicking that it turns out that this entire module is now deprecated. Says to use Phoenix.Component instead.
Correct! The live_patch helper is not deprecated in favor of the .link/1 function component. This is brand new as of LiveView 0.18 which was just released. We will be doing a big update of the entire book when LiveView hits 1.0 and we’ll update this and everything else at that time 
