I've seen candidates describe themselves as "Front of the Front-End" in the context of job interviews where the web UI stack included a BFF (Backend-for-Frontend, eg Next.js or Remix). It actually makes sense. The corresponding "Back of the FE" skillset encompasses proxy servers, API gateways, routing, observability, browser networking, server APIs, deployment infr, etc., on top of pure UI per se. There's a breadth of knowledge required that puts many backend-oriented "full-stack" devs to shame.