Earlier quoted context omitted.
What's your definition of full stack? Anyone that knows a back end language, sql, html and a bit of css and javascript is a full stack web developer.
I think you need to be able to debug a crash of the web server or kernel. This means C and at least a bit of a clue about assembly. I suppose it's OK to not be able to debug a hypervisor. On the other side of things, probably you also ought to be a competent artist and writer.
crash of the kernel => google the last error lines (hope you have one)