Shawn NgDeep dives into the hidden CS around you.
Long-form breakdowns of the algorithms and systems everyone uses and nobody looks at. Real systems, real numbers, no hand-waving.
The State of AI: A Field Report From Someone Who Actually Ships This Stuff
Halfway through 2026, the models are genuinely remarkable and the production reality is genuinely messy. A working engineer's account of what changed, what plateaued, and where the real work moved.
Local Models vs Frontier APIs: An Honest Accounting
What it actually takes to run LLMs on your own hardware, why memory bandwidth is the real bottleneck, and when the economics flip in favor of the API.
The Old Guard Refuses to Die: Classical Optimization vs the Learned Upstarts
Neural networks have been promising to replace exact optimization solvers for a decade. The solvers keep winning where it counts. Here is an honest scoreboard of classical methods versus learning-to-optimize, and the hybrid pattern that is actually emerging.
How Machines Learned to See
For forty years, computer vision meant hand-crafting features by hand and hoping. Then in 2012 a neural network cut the ImageNet error rate nearly in half, and everything we thought we knew about seeing turned out to be learnable. Here is the whole arc, from SIFT to vision transformers.
The 1947 Algorithm That Routes Every Package You've Ever Received
George Dantzig invented the simplex method as a tool for U.S. Air Force planning in 1947, and almost eighty years later it is still the workhorse that schedules airlines, blends gasoline, dispatches power, and routes the package on your doorstep. Here is how it actually works, with a Python implementation.
How YouTube Decides What You Watch
YouTube picks your next video by funneling billions of candidates through a two-stage neural pipeline: fast approximate retrieval, then a multi-task ranking model that predicts watch time, clicks, and satisfaction. Here is how the machine actually works, according to the published research.
The Math Problem That Protects The Entire Internet Is Dying
RSA and elliptic-curve cryptography secure almost every encrypted message on Earth, and a sufficiently large quantum computer running Shor's algorithm will break both. Here is how the math works, why it is fragile, and what post-quantum cryptography is replacing it with.
The Rejected Algorithm That Helped Land Us on the Moon
Rudolf Kalman's filter was rejected by an academic referee as "impossible." Nine years later, it guided Apollo 11 to the lunar surface, and today it runs inside every GPS, phone, drone, and self-driving car. Here is how it works, with a Python implementation.
The Scary Truth About Your Phone's SIM Card
Your SIM card is a full computer with a CPU, OS, filesystem, and network stack, running applets you did not install and cannot audit. Here is what is actually inside a SIM, how carrier applets like S@T have been exploited, and why the user has almost no defense against it.
The Bug That Killed the Lights for 55 Million People
How a race condition in power grid software caused the 2003 Northeast blackout, leaving 55 million people without electricity.
A* Pathfinding Explained: Why It Beats Dijkstra
Learn how the A* pathfinding algorithm works, why it outperforms Dijkstra, and see a Python implementation with heuristic functions.
Bellman-Ford Algorithm: How Traders Find Free Money with Graph Theory
How the Bellman-Ford algorithm detects negative cycles in graphs and enables currency arbitrage for finding risk-free profit.
Quantum Computers Have a Dirty Secret
Five fundamental limitations of quantum computing that explain why your laptop still beats quantum computers for most real-world tasks.
4 Data Structures Every Developer Should Master
Learn the four essential data structures every developer needs: arrays, hash tables, stacks and queues, and trees, with Python examples and time complexity analysis.
Why Cache Misses Are the Real Performance Killer
Understand how CPU cache misses destroy performance and learn cache-friendly coding patterns that can deliver up to 100x speed improvements.
The Hidden Magic of Hash Tables: How Your Computer Finds Anything in an Instant
Dive deep into how hash tables achieve O(1) lookups, including hashing functions, collision resolution strategies, and a Python implementation from scratch.
The Hidden Algorithm That Runs Your Life: Dijkstra's Algorithm Explained
Learn how Dijkstra's shortest-path algorithm works, powers Google Maps and internet routing, and where it breaks down, with a Python implementation.