I shut down the L train in a graph: max flow, min cut and AI agents on the New York subway
Picture 8 a.m. on a Wednesday in October. A signal fire in the Canarsie Tube stops the L between Bedford Av and 8 Av, in both directions, until furt…
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A(5) = 5: four matrices finish the case t = 5
This is from MV2's open notebook on Kakeya-type problems ( https://github.com/munimtechnologies/kakeya-small-fields ). It continues the earlier post…
Engineering a Multimodal Travel Planner on a 228,060-Edge Graph
A flight search engine answers a well-defined question: which available flights connect two airports? A door-to-door travel planner must answer a mo…
Why your topological sort gives a different answer on every run
You have a few tasks, and some of them depend on others. You put them in a graph, sort it topologically, and print the order. Then you run the progr…
How 913 Puzzles Became 7,304 Levels: Procedural Variation on a Precomputed Puzzle Bank
Meowdoku ships over a hundred levels and keeps growing. Every one of them has to be provably solvable. This is a Star Battle-style puzzle, so a malf…
ARM Matmul Continued: BFMMLA Edition
This is a continuation of my previous article on using ARM NEON to do matrix multiplication. Here's a fun one, we're going to use BFMMLA to do 2x4 @…
Implementing the Destiny Matrix in TypeScript: reducing a birth date to Major Arcana
The "Destiny Matrix" is a numerology-style system that went viral on social media: you enter a birth date and get a chart of numbers from 1 to 22, e…
SuperTrend Strategy Optimization: No Losing Year on Gold
Update, 21 Sep 2026. I put this result through a harder test after publishing, and the first optimized version below didn't survive it. The final, s…
Your RAG Searches by Meaning. But What About Exact Words? Meet BM25
Hello, I'm Rijul, and I'm building LiveReview — a blast-radius aware AI code review built for your business-critical systems. Star us to help devs d…
How Uber Computes Estimated Time of Arrival (ETA)
Short answer: how does Uber compute ETA? Uber snaps noisy GPS pings to the road network (map matching), finds candidate routes on a road graph, and…
Five results: I spent time proving splines don't help trajectory databases
If you work with GPS tracks, this idea shows up sooner or later: why store a trajectory as a polyline of thousands of points when a vehicle moves sm…
Building a Zero-Lag Client-Side Python Visualizer with Pyodide & WebAssembly
Understanding code execution, call stacks, and pointer mutations can be tricky—especially when debugging complex algorithms, recursion, or data stru…
Watch, don't memorize: I built a free visual way to finally understand data structures
You can read a hundred explanations of a linked list and still freeze when someone asks you to reverse one in an interview. You know the definition.…
I Compared 4 Dungeon Generation Algorithms. One of Them Never Works.
Four algorithms. Same grid. Very different dungeons. I implemented BSP trees, cellular automata, random walk, and room placement, ran each one 20 ti…
Solving the Implicit Colebrook-White Equation in TypeScript via Newton-Raphson Iterations
Fluid mechanics calculations in web applications often rely on simplified empirical approximations. When calculating friction losses in turbulent fl…
I spent months building an exact incremental-computation library in C. I finally put the reproducible benchmarks on GitHub.
I’ve been working on a performance project called HKD Kernel. The premise is that a lot of large computations repeat work unnecessarily. If only a t…
XGBoost Explained: From Gradient Boosting to Weighted Quantile Sketch
XGBoost Introduction: XGBoost XGBoost is a tree-based algorithm. It is a variant of Gradient Boosting which is one of the highest-scaled versions of…
How Does Ground Moving Target Indication Work? A Developer’s Guide to GMTI Processing
How Does Ground Moving Target Indication Work? Ground Moving Target Indication, or GMTI, is a radar processing capability used to detect moving obje…
Backtesting overfitting: why your backtest lies and how to make it honest
Cross-post. Original: stellarbytecapital.com/blog/backtesting-overfitting A profitable backtest is the easiest thing to produce in all of quant trad…
Monotonic Stack: The Matrix of Array Problems
The Quest Begins (The “Why”) Ever spent an hour wrestling with a brute‑force solution that felt like you were trying to break through a concrete wal…
Dynamic Programming: The Matrix of Patterns
The Quest Begins (The "Why") I still remember the first time I saw a dynamic programming question pop up on a whiteboard during an interview. The pr…
22 tests passing, and my solver still told you to click a mine
I wrote a minesweeper probability solver. You hand it a board, it hands back the probability that each unknown square is a mine, so that when logic…
I built a crypto trading bot. It lost to doing nothing.
Every trading bot post ends the same way: a green equity curve and a suspicious silence about whether it made real money. This post is the other one…
Algorithmic Patterns: The Ultimate Guide to Sliding Window
The Sliding Window pattern is one of the most vital algorithmic techniques for optimizing array and string problems. Instead of repeatedly processin…
Greedy Algorithms: Choosing Your Path Like Neo in The Matrix
The Quest Begins (The "Why") I still remember the first time I stared at a whiteboard covered in overlapping intervals during a mock interview. The…
Optimizing LLM Context for OpenAPI: A Deterministic Approach to Token Reduction
How deterministic context batching reduced approximate token usage by ~81.7% while building an agentic API testing prototype See It in Action I also…
Why I use reconstruction puzzles to keep interview algorithms fresh
The hardest part of algorithm interview prep was not learning binary search or two pointers for the first time. It was opening an old problem months…
How We Evolved a Cultural Recommendation Feed From a Weighted SQL Ranker to a Narrative Affinity Model
Building a personalization engine for a multi-format content feed, without machine learning, and the testing process that forced us to rebuild it. T…
ESPBanking By Dumasha
Hello, I am presenting my project ESPBanking, It is a simulation of a Bank system with RFID System, Security, Web UI and much more. I got that Idea…
Extreme Combinatorial Optimization in VRAM: Architecture and Engineering of AETPC
The Challenge of Combinatorial Complexity Large-scale combinatorial optimization problems—such as the classic Traveling Salesperson Problem (TSPLIB)…