The worked example that disagreed with its own calculator
I run a small site of home-improvement cost calculators ( costto.build ) — pick a project, get a low / average / high estimate with a materials-and-la…
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Open Graph Image Sizes and Dimensions: The Complete 2026 Guide
When you paste a link into Slack, X, or iMessage and it unfurls into a rich card with a big image, that image comes from your page's Open Graph tags. …
How to E2E Test SendPigeon Email Workflows in Playwright
When you integrate SendPigeon into your app, you get three stages of email testing. Each stage solves a different problem. This guide walks through al…
Why PDF generation breaks in production (and why localhost lies)
PDF generation is one of those things that works perfectly… until real users touch it. On localhost: npm run dev Open Chrome → print → PDF. Done. Then…
Stop refunding payments you should never have charged
I once shipped a checkout that charged the card the instant the customer hit pay, then ran the order validation afterward. Stock check, address valida…
Auto-Block Focus Time in Google Calendar — Building a Schedule-Based Chrome Extension
Most focus-time tools for Google Calendar require OAuth access and sync your calendar data to their servers. Clockwise shut down its free tier. Reclai…
TypeScript Without tsc in 2026: Type-Stripping in Node.js 24, Bun, and Deno Compared
TypeScript Without tsc in 2026: Type-Stripping in Node.js 24, Bun, and Deno Compared The End of tsc: Why Type-Stripping Changed Everything in 2026 Mos…
I built an Aadhaar QR reader that works 100% offline — no server, no data leak
Every time I handed my Aadhaar card to someone for KYC, one thought kept nagging me: Where is this data actually going? Most "digital Aadhaar verifica…
A Korean Saju (Four Pillars) API that gets the date math right
If you have ever tried to build a Korean fortune-telling or astrology app, you already know the dirty secret: the fun part is the interpretation, and …
How I built Google Drive sync without a backend (and the 3 bugs that almost broke me)
When I started building PenPage — a privacy-first note app that stores everything in IndexedDB — I made one assumption that cost me three weeks of deb…
Stop Parsing PDFs at Render Time: A Better Architecture for Structured Extraction
TLDR: The reason most frontend PDF extraction is wrong is that developers try to infer document structure from the rendered visual output instead of f…
The Code AI Won't Write
I use a form validation problem as a technical interview question. It's deceptively simple — and the solutions people reach for reveal a lot about how…
Handling Shadow DOMs in Agentic Scraping Workflows
TL;DR Web components encapsulate UI and data inside Shadow DOMs, hiding it from standard parsers like BeautifulSoup and document.querySelector . To ex…
The Day AI Argued With MDN (And Lost)
AI coding assistants have changed how we write software. They generate components, explain APIs, write tests, and even review pull requests. But there…
Day 32 of Learning MERN Stack
Hello Dev Community! 👋 It is Day 32 of my continuous web development run, and today I jumped into a project that pushed my array manipulation and cond…
Wuchale: One Year of Compile-Time i18n
Photo by Bernd 📷 Dittrich on Unsplash It has now been one year since the initial commit of Wuchale! A lot has happened since then and I will explore s…
The exact math that made $40,000,000 out of Polymarket (Full roadmap)
While you're manually checking if YES + NO = 1 , quantitative systems are solving massive constraint satisfaction problems across thousands of correla…
package.json vs go.mod: Where Did the Version Field Go?
If you come to Go from JavaScript, one small thing surprises almost every developer. Open any package.json . Look near the top. It is always there: { …
The Day We Fixed Our Signup Pipeline
It started with a graph. Our signup numbers were climbing every week. The team was excited—growth was happening. But something felt off. A lot of thos…
Escaping the Trap: Fixing Stale Closures in React Hooks ⚡
The Silent Interval Bug When building dynamic dashboards at Smart Tech Devs, you frequently need to implement background timers. Whether it's an auto-…
TypeScript 6.0 Released: The Last JavaScript-Based Version — New Features, Breaking Changes, and Migration Guide
TypeScript 6.0 Released: The Last JavaScript-Based Version — New Features, Breaking Changes, and Migration Guide TypeScript 6.0: The End of an Era and…
We Deleted Our Focus Trap, Scroll Lock, and Toggle Logic — The Browser Already Does It
A few weeks ago I went through every "headless UI primitive" in @snatuva/primitives — our Angular signals-first, unstyled component library — and star…
How I Built a Zero-Dependency Token Compressor for AI Coding Agents (During My High School Exams)
as developers, we are spending more and more time working alongside AI coding agents like Cursor , Claude Code , GitHub Copilot , Windsurf , or Cline …
How I Built a Cinematic Portfolio with React and Framer Motion
Hi, I'm Akshay Bhawar, a Full Stack Developer from Maharashtra, India. Recently, I decided to completely redesign my portfolio. Instead of going with …
Biome vs Oxlint in 2026: Which Rust-Powered Linter Should You Replace ESLint With
Biome vs Oxlint in 2026: Which Rust-Powered Linter Should You Replace ESLint With Most teams replacing ESLint in 2026 choose the wrong Rust-powered li…
I built a JS/TS runtime in Rust where nothing runs without your permission
Last week I shipped v2.0.2 of 3va — a JavaScript and TypeScript runtime written in Rust. Here is why I built it and what makes it different from Node.…
I built a 1:1 solar system with Fable 5 in the days before it was pulled offline
I built a 1:1 solar system with Fable 5 in the days before it was pulled offline On June 9, Anthropic released Claude Fable 5 — the most capable model…
I built a JS/TS runtime in Rust where nothing runs without your permission
Last week I shipped v2.0.0 of 3va — a JavaScript and TypeScript runtime written in Rust. Here is why I built it and what makes it different from Node.…
OTP Verification in Playwright Without Regex
Every developer who has written a Playwright test for OTP verification has written this line: const otp = email . body . match ( / \b\d{6}\b / )?.[ 0 …
Why recording video in the browser is harder than it looks
Hey folks! In this article, I want to share our experience building a screen recorder inside the browser. The product is Browser Recorder , a Chrome e…