📰 Dev.to · SEN LLC

A Hello World Museum for 84 Languages — and the Round-Trip Test That Makes a Tiny Syntax Highlighter Trustworthy

A Quiz Is Only as Good as Its Wrong Answers — Building Algorithmic Distractor Generation for a Japanese Idiom Quiz

Try the Tech Radar #6 (Final) — Semantic Layer in 200 Lines: One Definition, Many SQL Consumers

Try the Tech Radar #3 — JSON Schema LLM Prompt, Visualised

Try the Tech Radar #2 — Markdown Typst Converter (Typst's Syntax Is Closer to Markdown Than LaTeX)

Try the Tech Radar #1 — TOON Cuts JSON Token Cost by 71% for LLM Context

A Visual CSS Grid Builder in 500 Lines — How fr, minmax, and repeat Actually Compute Sizes

An npm Downloads Comparison Chart in 300 Lines of Vanilla JS — Nice-Tick Math and API-Direct Fetch

Building a Mini Tailwind-to-CSS Converter — How Utility Class Names Map to Real CSS

Building a Chord Progression Generator in the Browser — Music Theory in JS, Sound via Web Audio API

Visualizing 4 Sorting Algorithms with JavaScript Generators — O(n ) vs O(n log n) in Real Time

A Math-Expression Parser in 250 Lines of JavaScript — Recursive Descent, Right-Associative ^, and -2^2 = -4

Computing Moon Phase in 150 Lines of JavaScript — Julian Date, Synodic Month, and SVG Terminator

A Browser IPv4 CIDR Calculator — Three JavaScript Gotchas (uint32 Coercion, /0 Shift Trap, RFC 3021 /31)

A Browser-Only Diary in 350 Lines — Month-Grid Math, Code-Point Character Counts, and Streak Boundaries

Plotting 5 Years of FX in the Browser — Frankfurter API + Hand-Rolled SVG Line Chart

Reimplementing path-to-regexp in 100 Lines — Why /users/:id? Almost Never Works the Way You Expect

Visualizing A* One Node at a Time — The Tie-Break and Corner-Cut Decisions That Decide How the Demo Looks

A 350-Line GLSL Shader Playground in the Browser — WebGL Init, Line-Number-Aware Errors, and URL-Hash Sharing

A Browser Ear-Training Trainer in 350 Lines — Equal-Temperament Frequencies and Three Web Audio Footguns

A Real-Time Earthquake Map for Japan in 300 Lines of JavaScript — USGS GeoJSON + Leaflet

Searching Emojis With Casual Japanese Keywords — Why Unicode CLDR's ja Annotations Aren't Enough

Reading Apple Pencil Pressure in the Browser — PointerEvent, getCoalescedEvents(), and the e.pressure Trap

csv-peek — A 700-Line Rust CLI That Pretty-Prints CSV in the Terminal With a Hand-Rolled RFC 4180 Parser, Type Inference, and One Dependency