Nine puzzle solvers, one browser tab, zero servers: a tour of classic search algorithms
I recently finished building a small suite of puzzle and game solvers that all run entirely in the browser — no backend, no API calls, no machine-le…
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HLD: Instagram Feed
Design a photo-sharing platform where users post photos and see a feed of photos from people they follow. 1️⃣ Clarify Requirements Functional Requir…
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…
Learn Valid Parentheses, Reverse Linked List, and Tree Max Depth with Step-by-Step Visualization in DSA View View 👀👀
Hoi hoi! I’m @nyaomaru , a frontend engineer who struggles to make game sounds. 😿 Have you used DSA View View already? 👀👀 I Built a Tool to Visualiz…
Building a TypeScript Code Radar: What an AST Reveals That Text Search Misses
Today I started experimenting with Tree-sitter . I had heard the name before, but I had never actually used it. My goal was simple: take a TypeScrip…
Functions Behind the Scenes
Why should you care? You use functions constantly: int result = add ( 10 , 20 ); It looks simple. You call a function, it does some work, and it ret…
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…
Designing Algorithms That Adapt to Their Input Distribution
Most algorithms are taught as if the input were some abstract thing that simply arrives at the function boundary. An array appears. A graph appears.…
Binary Search: The Matrix of Algorithms – Patterns, Edge Cases, and Real Interview Questions
The Quest Begins (The "Why") I still remember the first time I bombed an interview because I tried to solve a “find the target in a sorted array” qu…
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…
Why Fixed-Window Rate Limiters Fail (And How to Fix Them with Math)
If you’ve ever built an Express API, you’ve probably reached for standard rate-limiting middleware to protect your login or payment endpoints from D…
You don't search for the key, you search for English: how cipher auto-solvers actually work
You've figured out which cipher you're staring at — say a monoalphabetic cryptogram, or a Vigenère — but you don't have the key. No keyword, no shif…
Building a Fast Word Unscrambler: The Algorithm Behind Anagram Solving
I recently built WordScrambler, a free tool for unscrambling letters and solving anagrams, mostly out of frustration with existing tools being clutt…
LeetCode 3116 (Hard) — binary search + inclusion-exclusion makes it easy
Full walkthrough: https://www.youtube.com/watch?v=vFuFA3ByCs0 LeetCode 3116 — Kth Smallest Amount With Single Denomination Combination. Here’s the t…
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…
Watch a Game AI Think: Minimax and Alpha-Beta, in a Browser Tab
Every "AI" opponent in a board game — Tic-Tac-Toe, Connect 4, Checkers, Othello, Chess — tends to run the same idea: search the game tree, assume th…
Building a Location-Aware Discovery Engine: Why “Nearby” Isn't Just Distance
"Nearby" sounds like a simple feature. Calculate the distance between the user and every location. Sort by distance. Done. In practice, that's not e…
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…
I built a content recommender as a graph, and it found similarities I wasn't looking for
Most beginner recommendation projects are a dictionary lookup. You type "comedy", it returns the comedy list. That works, and it is also the reason…
The Matrix of Tree Traversals: Recursive vs Iterative Explained
The Quest Begins (The "Why") I still remember the first time I was asked to validate a binary search tree in an interview. My brain went into panic…
Graph Theory in C#
Using graph search to solve real-world problems in C# Most day-to-day C# work involves flat collections: filter a list, sort a table, look something…
An O(1) Space Alternative to "Rearrange Array Alternately" Using Sequential Suffix Reversal
If you've spent time on LeetCode or GeeksforGeeks, you've probably run into the classic "Rearrange Array Alternately" problem. The premise: given a…
Variables Are Memory Addresses
Variables Are Memory Addresses Why should you care? You write: int age = 20 ; It looks like age is simply a box containing the number 20 . But what…
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…
How We Made Image Copy-Detection ~1,000,000 Faster — by Refusing to Look at Pixels
Structural hashing for pixel art: a 1024-byte key that answers 'is this the same artwork?' in 115 nanoseconds — and then tells you exactly what was…
Why Route Ranking Needs Deterministic Scoring, Not a Language Model
When you build a tool that compares travel routes: flight vs. train vs. bus, the obvious instinct is to let a language model read the variables and…
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…