Algorithms and Data Structures in TypeScript – Free Book (~400 Pages)
I started writing this book 10 years ago in JavaScript, got through a few chapters (asymptotic notation, basic techniques, start of sorting), and then abandoned it. Recently I picked it back up, converted everything to TypeScript, and used AI (Zenflow [1] + Claude Opus 4.6) to complete the remaining chapters. I provided the structure, direction, and initial chapters; the AI generated the bulk of the remaining content under a spec-driven workflow. The book covers roughly a first 1-2 year CS curriculum: sorting, dynamic programming, graph algorithms, trees, heaps, hash tables, and more. All…
In plain words
This free, open-source book covers core computer science topics including sorting, dynamic programming, graph algorithms, trees, heaps, and hash tables in TypeScript. Written over a decade and completed with AI assistance, it provides approximately 400 pages of executable, typed code with comprehensive tests. The book targets students and developers learning fundamental algorithms and data structures, offering practical implementations suitable for a first one-to-two year CS curriculum. All code examples are runnable and tested, with the material available under an MIT license.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
I started writing this book 10 years ago in JavaScript, got through a few chapters (asymptotic notation, basic techniques, start of sorting), and then abandoned it. Recently I picked it back up, converted everything to TypeScript, and used AI (Zenflow [1] + Claude Opus 4.6) to complete the remaining chapters. I provided the structure, direction, and initial chapters; the AI generated the bulk of the remaining content under a spec-driven workflow. The book covers roughly a first 1-2 year CS curriculum: sorting, dynamic programming, graph algorithms, trees, heaps, hash tables, and more. All code is executable, typed with generics/interfaces, and covered with tests. I've thoroughly reviewed several chapters (sorting, DP, graphs) and done a high-level pass on the rest. Currently in beta — corrections and contributions are welcome. MIT licensed. Inspired by Wirth's "Algorithms and Data Structures", SICP, and CLRS. Code and tests: https://github.com/amoilanen/Algorithms-with-Typescript [1] https://zencoder.ai/zenflow
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