It's near the top of the individual contributor (ie. non-manager) job ladder.

L5 = senior L6 = staff L7 = senior staff L8 = principal engineer L9 = distinguished engineer L10 = fellow

None of these are titles that Google invented, btw.

yes, an L9 is roughly a guild navigator but the MKs stopped serving spice 10 years ago

My bad, seeing as it's roughly between chief science officer and the (less bourgeoise and more Google-ish) Lord of Sith.