Can you survive being a pure backend or frontend developer?
Knowing the differences between a backend and a frontend developer is just a theory, but the practice is usually different. When facing a real task in a website project there will be many times that will require you to have knowledge on backend and frontend. You do not need to have a deep knowledge on both areas, but you need enough.
After some time, you have spent more time reading about backend topics than actually implementing the feature. And this can be applied to backend developers too.
Web developers should be ready to learn whenever is needed, adapting to the needs of the project. So you cannot say “sorry but I know nothing about that”, but “ok, I will work on it” and go ahead learning while you work on the feature.
Imagine a product page. That page is being loaded in a classic way, with or without Turbolinks. But business needs it converted to Ajax and display a loading image, and after it’s done, update some part in the page. Is it worth calling a backend developer and work together on it? It depends on the current workload, but even if that developer is free, everyone would expect you to learn about the backend framework so you can implement the remote link, save the JS code where it belongs, and so on. And yes, by yourself. Or course you can ask questions, and you should be encouraged to do so, but the general idea is to be independent. This is specially important if you work remotely.
You definitely need to adapt.