As in, either at an early age or early in their career.
Because I'm 26 with about 3-4 years of experience (maybe 5 if I count my apprenticeship), and my company keeps reiterating how they promote based on skill and knowledge, and not based on age. I know that I fit the soft skill requirements for senior dev on the internal checklist. And I know that I could absolutely handle the 6-week project that potential Seniors are asked to do, because all of my experience is extremely specialized into the exact current field and position I work at.

So I'm playing with the idea of asking to become a senior next year, because I plan on leaving the company and the title would look good on my resume.

Does anyone around here have experience with doing something like that?