Ritchie Vink (the creator of Polars) deliberately decided not to write a book so that he (and his team) can focus full time on Polars itself.
Thijs Nieuwdorp and I are currently working on the O'Reilly book "Python Polars: The Definitive Guide" [1]. It'll be a while before it gets released, but the Early Release version on the O'Reilly platform gets updated regularly. We also post draft chapters on the Polars Discord server [2].
The Discord server is also a great place to ask questions and interact with the Polars team.
Thijs Nieuwdorp and I are currently working on the O'Reilly book "Python Polars: The Definitive Guide" [1]. It'll be a while before it gets released, but the Early Release version on the O'Reilly platform gets updated regularly. We also post draft chapters on the Polars Discord server [2].
The Discord server is also a great place to ask questions and interact with the Polars team.
[1] More information about the book: https://jeroenjanssens.com/pp/
[2] Polars Discord server: https://discord.gg/fngBqDry