Henry Ndubuaku, a Y Combinator alumnus, has released an open-source textbook titled "Maths, CS & AI Compendium" on GitHub. The resource aims to provide intuitive, real-world explanations of mathematics, computing, and artificial intelligence concepts, targeting curious practitioners rather than exam-focused students.
The compendium originated from Ndubuaku's personal notebooks, which he used to prepare friends for interviews at top AI labs like DeepMind, OpenAI, and Nvidia. According to the author, all of those friends secured positions and perform well in their roles. The repository also includes an MCP server that allows AI assistants such as Claude Code and Cursor to use the compendium as a knowledge base.
Learning Philosophy and Techniques
The textbook emphasizes that quality knowledge consumption and execution intensity matter more than raw IQ. Ndubuaku draws an analogy between a newborn's brain and a newly initialized neural network that trains on real-world data. He cites Kvashchev's experiment, a Serbian study showing that intensive creative problem-solving training can boost fluid intelligence by 10-15 IQ points.
Ndubuaku shares his personal learning journey: after struggling academically when he relied on natural ability, he adopted a two-phase study technique. The first phase involves cumulative reading after each lecture, reviewing material before bed and then restarting from the beginning before the next class. The second phase, used before exams, is shadow reading: he reads subtitles, closes the book, and writes explanations from memory, only re-reading missed parts. He compares this to masked-language modeling in machine learning.
Accessibility and Background
The compendium requires only elementary mathematics and basic Python programming. Ndubuaku notes that the academic system often favors fast learners, but this resource is designed for "the Darwins of the world"—a reference to Charles Darwin, who was considered a below-average student by his teachers. The author's own experience reinforces this: after dropping to the bottom half of his class between ages 11 and 13, he became a diligent reader and finished first in his final secondary school semester. The textbook is available for free on GitHub, and Ndubuaku encourages readers to "trust the process."