Software engineer titles are a mess. Senior Software Engineer title got deflated over the years. It's not uncommon to see people with 3 years of experience with it. As a result technical career path becomes problematic as there is none. As an obvious solution new titles started appearing. Company started to create their own titles, which doesn't tranfer or communicate much outside the company. The most common title above the Senior in Australia is Lead Developer, but that's pretty much it.
Recently I've discovered a new title taxonomy called Staff Engineering. It is still loosely defined. This book is based on aggregation of opinions and defines the next technical levels above Senior.
The book has lower quality than I'd expect from books. It feels like a collection of blog posts. However it's still useful to read to get the authors opinion.