Hey Harvey! Thanks for asking this question!
I think if you have already decided where you want to be, then you don't need to worry about anything frontend! There are front end developers, there are backend, then there are areas that have NOTHING to do with websites! You can work in everything that has nothing to do with a frontend. Just make sure you have really learned a deep level in the languages you are trying to specialize in and you can pass a hackerrank questions. You should be in good shape then.
Hope this helps.