This setup is deviating quite a bit from a default rails setup: using the beta webpacker, tailwind + plugins, some extra gems. Also - I noticed the author says

This setup is deviating quite a bit from a default rails setup: using the beta webpacker, tailwind + plugins, some extra gems. Also - I noticed the author says "foreman is the best way to develop locally". I encourage the author to give overmind a try - it is a drop in, more featureful replacement for foreman. I love it.