Show HN: I Wrote a 680-Page Interactive Book on Data Structures and Algorithms

13 EliasY 4 7/17/2025, 2:17:07 PM cartesian.app ↗
Hello HN! I’m Elias.

I’ve been an educator in Engineering and Computer Science for some years, and I'm always looking for ways to make learning more engaging and hands-on. A few months ago, I started experimenting with the idea of a book that changes and evolves as you interact with it. It started with a chapter on sorting but that snowballed into a 22-chapter interactive book.

My objective in writing this book, was to introduce a more interactive format for technical books that doesn't require internet access, that is lightweight, comprehensive, cross-platform, and can provide a better active learning experience.

Some unique features of the book include:

* 22 Chapters of condensed theoretical treatment spanning 680 pages, on simple and complex data structures and algorithms, paired with over 300 interactive visualizations.

* Code snippets presented in the book can be interacted with, and feature a visual debugger that shows how variables change as the program runs. You can also play, pause, rewind, and step through each snippet.

* There are a variety of solved problems under each topic accompanied by an embedded minimalist python IDE. You can solve problems directly in the book, view multiple solutions with each solution paired with interactive visualisations and code playback.

The book is currently out and available here: https://cartesian.app

Students can also DM me on Twitter (@ElijahYilma) to get an additional 35% discount.

Past Discussion on Reddit: https://www.reddit.com/r/SideProject/comments/1liga56/i_wrot...

I’d love any feedback or improvements you may have, and more importantly, which topics you would like to see covered in this format (CS and non-CS).

Comments (4)

u_sama · 6h ago
Just as a heads up, I find your thing interesting but in the EU it is illegal to sell a service and not provide a refund policy. This is the main reason pushing me to not actually purchase it.

Some sourced: [0] - https://europa.eu/youreurope/citizens/consumers/shopping/gua... [1] - https://www.termsfeed.com/blog/return-refund-laws-eu/

EliasY · 6h ago
Huh... I didn't know about this! But FYI I only wrote the no refund policy as a means to prevent/discourage refund abuse, as the product is only available digitally. I have however refunded two people who have requested a refund. But I completely understand your take!
yogini · 5h ago
the book looks useful for beginers to visualise and understand concepts better. Alignment of table of contents and FAQ section is breaking on larger screens. I will share this one on Peerlist as well, many devs their might find it useful.
EliasY · 5h ago
The screen resolution issue seems to stem from the fact that I've locked the book to a 16:9 aspect ratio, and I'm still working on it. Thank you for sharing it as well!