CrackingWalnuts
Most things are harder to understand than they look, not because they are complicated but because most material stops too early: at the surface, at the abstraction, at the explanation that feels good enough. Like a walnut, the interesting part is inside the shell, in the structure and trade-offs you only see once you pull things apart. That is what Cracking Walnuts goes after.
It is a platform for two things: learning the craft and cracking the interview. Across 24+ tracks you get full courses, worked examples, code in five languages, and interactive tools that let you play with the hard ideas instead of only reading about them. It runs from entry level to engineering leadership.
Useful engineering knowledge is scattered across docs, talks, and conversations that never get written down clearly. Cracking Walnuts pulls it together and deals with the real trade-offs and failure modes instead of pretending there is always a clean answer.
Every lesson is worked by hand with small numbers and diagrams, then connected to how it shows up in real systems and real interviews. The goal is simple: you leave understanding the thing, not just remembering an answer.
Working Staff Engineers, Principal Engineers, and Engineering Leaders. People who have built these systems, led the teams, and run the hiring loops.
They are still in those roles today, which is why everything here ships under the Cracking Walnuts name and not under personal ones.
You do not have to take that on trust. Every track keeps one full lesson open, so you can judge the work for yourself.
How large language models actually work, and how they run in production. Transformers and attention, tokenization, embeddings and vector search, RAG, inference serving, and training infrastructure.
Algorithm patterns and clean object-oriented design, the building blocks behind every coding and machine-coding round. Templates you can reach for under pressure.
Consensus, replication, sharding, multi-tenant architecture, and the patterns behind systems that scale. Real trade-offs and failure modes, not textbook answers.
Threads, locks, channels, and async across Java, Python, and Go. Where real systems get fast, and where they quietly break.
TCP, HTTP, TLS, DNS, QUIC, and BGP. The protocols that move data across the internet and why they matter.
Telling your story by level, from entry level to principal. Plus the leadership, org design, and influence that staff-plus roles actually run on.
Play with the hard ideas instead of just reading about them. Consistent hashing, rate limiters, CAP, load balancers, and back-of-envelope math you can poke and tweak.
Questions, feedback, or a correction? The Cracking Walnuts team would love to hear from you.
Ready to dive in?