I’ve only done product demos, but I’ve had a lot of success with react frontend statically served using a static plug with API endpoints defined in plug, dispensing with most of Phoenix (plug underlies most Phoenix routes)

You’ll want a “catchall” in your router..

what urls are you using in the react app?

say you are using /admin and the controller is PageController index

  scope "/admin", MyApp.Web do
    pipe_through(:browser)
    get("/*path", PageController, :index)
  end

then hitting /admin/login will fire up the react app..

if you haven’t “scoped” you react with /admin or /app or similar I think you’ll need to be explicit eg.

  scope "/", MyApp.Web do
    pipe_through(:browser)

    get("/", PageController, :index)
    get("/login", PageController, :index)
   #etc
  end