I picked this up after finishing "The Rust Programming Language", in parallel with starting to write my own first crates and contributing to others. It's a great overview of the more advanced topics in the Rust ecosystem; not just the language itself but also the various libraries and tooling around, like cargo. I feel it's mostly useful to understand what's out there and where to look for more detail if needed. For example, if I need to benchmark code in more detail I know now which libraries and APIs will be relevant to me.

Since this book covers more advanced topics, it also talks a lot about non-stabilized APIs and features, so it ages a bit less well than TRPL; some of the content is already outdated after a good year. But that really shouldn't stop you from reading it, the concepts explained in this book are still super relevant.

"By the way" the author also has great video material on youtube with deep dives into various aspects of Rust, so go have a look at that too! :)