react-scripts start is doing hot recomplile to the server in-memory as far as I can tell not touching the build/* folder

react-scripts build is doing a one-time compile to build/* generating new scripts.

I want to hot compile to build/* so I am not doing CORS (doing some security testing and need to operate like it is in production where the website hits the backend it is served from but would prefer to do so with live changing react app – albeit via browser refresh button).

How to do this correctly as it seems react-scripts has some watch functionality?

I tried many posts on webpack resulting in all sorts of erros, and babel as well as npx tsc –watch which seemed to not compile anything. I am getting lost in too many posts with none of them working.