I have a little more than four years of experience, and luckily I have had the chance to work across backend, frontend and DevOps. I would say shipping and designing backend systems is still my forte, very shortly followed by Devops and frontend work.
Whilst I want to continue growing wrt my backend skills, my immediate focus is to get my DevOps and backend skills right upto to where my backend skills are.
When you have 4+ years of experience, I would expect you to take ownership of individual modules and ship them, so knowing things across the stack is a necessity I would think.