PDF link: https://raw.githubusercontent.com/LaurentRosenfeld/think_raku/master/PDF/think_raku.pdf

Subtitle: How to Think Like a Computer Scientist. If you haven't looked into Raku yet, you can read this article to get an idea of what's so exciting about it.

Here's the book's entry on the website of co-author Allen Downey.

License: Creative Commons BY NC 3.0 Unported.