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In part 1, we built the shared mental model: call stack, microtask queue, macrotask queue, and the rule that microtasks fully drain before the next macrotask runs. That model is spec-level JavaScript behavior — but it's not the whole story once you actually run code. The event loop isn't part of the JS language spec. It's part of the host environment — the browser or Node — and each one implements it differently around that shared core. This is the post most "event loop" explainers skip, because it means going past the diagram and into how each runtime is actually built. The browser: event loop meets rendering In a browser, the event loop isn't just juggling callbacks — it's also responsible for keeping the page visually responsive. That means rendering has to get a turn too, and the browser has to decide when . Here's the roughly accurate sequence per loop iteration: Execute one macrotask (a click handler, a setTimeout callback, a network event, whatever's next in the queue) Drain the entire microtask queue Maybe render a frame — the browser doesn't render after every single task; it tries to hit ~60fps and will batch work between paints Go back to step 1 The "maybe render" part is where two APIs come in that don't exist in Node at all: requestAnimationFrame(callback) — schedules a callback to run right before the next repaint. It's not a macrotask or microtask in the queue sense — it's tied directly to the rendering pipeline. Use it for anything visual (animations, DOM measurements) instead of setTimeout , because it's synced to when the browser is actually about to paint, not an arbitrary delay. requestIdleCallback(callback) — schedules a callback to run when the browser is idle, after layout and paint, with a deadline. Meant for low-priority work you don't want competing with rendering — analytics, prefetching, non-urgent DOM updates. Here's the key interaction that's easy to miss: microtasks can starve rendering. If a promise chain keeps queueing more microtask

"Because typing the same 15 commands every day is so 2026." A command-line utility that turns your chaotic terminal sessions into a beautiful, interactive menu. Stop memorizing commands. Start executing like a pro. 🚀 What Makes This Tool Special? Feature What It Does For You 🎯 Zero Memorization Never type kubectl get pods --all-namespaces --context=prod again ⚡ Lightning Fast One binary. No dependencies. Runs everywhere. 🔗 Command Chaining Execute complex workflows with --exec "1-2-3-4" 📁 Team-Ready Share menu.yml with your team. Onboard new devs in 30 seconds. 🔐 Env Variables Store secrets safely in env.ini — never hardcode credentials 📦 Installation (30 seconds or less) Option 1: One-Liner (if binary is hosted) curl -sSL https://example.com/hello | sudo tee /usr/local/bin/hello && sudo chmod +x /usr/local/bin/hello Option 2: Build from source git clone https://github.com/yourrepo/hello cd hello go build -o hello main.go ./hello --help Option 3: Copy & Go # Anywhere you want: cp hello ~/hello # Home folder cp hello /usr/local/bin/ # Global access (recommended) 🎮 Usage That Will Make You Smile Interactive Mode — The "I'm Feeling Lazy" Way # Just run it. The menu will greet you. ./hello # Using your own config ./hello -c ./deploy_menu.yml Headless Mode — The "I'm Automating Everything" Way # Execute a single command ./hello --exec "1" # Execute a whole pipeline (1 → 2 → 3 → 4) ./hello --exec "1-2-3-4" Perfect for: CI/CD pipelines, morning standup scripts, and impressing your boss. 📂 Example Menu (Your New Best Friend) items : 1 : title : " 1. 🚀 Deploy to Production" commands : - " git checkout main" - " git pull origin main" - " docker build -t myapp:latest ." - " docker push myapp:latest" - " kubectl rollout restart deployment/myapp" 2 : title : " 2. 📊 Check System Health" commands : - " htop" - " df -h" - " free -m" - " netstat -tulpn | grep LISTEN" 3 : title : " 3. 🔥 Clean Up Docker Garbage" commands : - " docker system prune -af --volumes" - " echo '✨ Saved 47 GB

Most of the validation work on vaas-x so far had been industrial sensor data — turbofans, machine telemetry. I wanted to know if the same zero-config channel classifier actually transfers to a completely different domain: a wearable IMU strapped to a moving human. No feature engineering, no per-sport tuning, no hints about what any channel means. I'm writing this one up slightly differently than my other posts, because the first version of this test gave me a wrong answer, and I think the reason it was wrong is more useful than the result itself. The dataset UCI's Daily and Sports Activities set (Altun, Barshan & Tunçel, 2010): 8 subjects, each wearing five Xsens IMU units — torso, both arms, both legs — 9 axes per unit (accelerometer, gyroscope, magnetometer × x/y/z), sampled at 25Hz. 45 channels total. It includes both a sedentary activity (sitting) and dynamic sport activities (basketball, rowing), which gives a clean, checkable question: does a classifier that's never seen this data correctly tell apart "person sitting still" from "person playing basketball," using channel statistics alone? import pandas as pd # Mirrored subset: github.com/AniMadurkar/Daily-Activities-and-Sports-Biomechanics-Analysis df = pd . read_csv ( " sports_science_dataset_subset.csv " ) channels = [ c for c in df . columns if c not in ( " subject " , " activity " , " timestamp " )] print ( len ( channels ), " channels " ) # 45 First attempt — and the mistake My first pass pooled all 8 subjects together per activity and ran it through the profiler in one shot. The result came back backwards: sitting showed up with more "significant" channels than basketball. That's not just unexpected, it's physically nonsensical — a person sitting still should be one of the lowest-variance activities in the entire dataset. The bug wasn't in the classifier. It was in the test. Pooling subjects together means each subject's own sensor baseline and IMU orientation differences get mixed into the between-subje

BMW is forcing a weird Spider-Man ad onto its dashboard displays

Quotient CEO Lizzie Matusov explains why soaring AI spend often fails to improve software delivery. She presents a research-backed AI maturity framework designed to help engineering leaders move beyond vanity metrics like token usage, align organizational AI adoption, and address critical bottlenecks across the software development life cycle to deliver measurable business outcomes. By Lizzie Matusov

When you start as a junior developer, you think software engineering is about writing code. A few years in, you think it's about choosing the right architecture and frameworks. After ten-plus years in the trenches - shipping features, surviving on-call disasters, and watching "perfect" codebases turn into unmaintainable monsters - you realize the truth: Software engineering is mostly about managing complexity, human communication, and trade-offs. Here are 25 mistakes I made, witnessed, or had to clean up over the past decade. Hopefully, reading them saves you a few years of painful trial and error. 1. Code & Architecture 1. Abstracting Too Early The DRY (Don't Repeat Yourself) principle is heavily drilled into beginners, but premature abstraction is far worse than duplicate code. Abstracting before you have 3–4 concrete use cases leads to rigid, over-engineered abstractions that are nightmare-inducing to change. Duplication is far cheaper than the wrong abstraction. 2. Falling in Love with "Clever" Code If your code requires a three-minute internal monologue or a complex diagram just to parse a single line, it's not smart - it's a liability. Write obvious, clear, and boring code. Your future self on a 2 AM incident response call will thank you. 3. Misunderstanding the Cost of Dependencies Adding a third-party library to solve a small problem feels like a quick win. In reality, every dependency is a contract you sign with an external team. You inherit their bugs, security vulnerabilities, breaking updates, and maintenance cycles. Ask yourself: Can we build the 5% of this library we actually need in 20 lines of code? 4. Over-Architecting for Scale You Don't Have Designing a system for 10 million daily active users when you currently have 500 is a classic trap. You end up with distributed microservices, message queues, and complex caching strategies that slow down development speed by 10x. Build for today's scale, but keep the boundary clean enough to refactor tomorrow

This is my official entry for the Frontend Challenge - Comfort Food Edition under the CSS Art category. Inspiration 🍚🐟 When thinking about "comfort food," I didn’t want to pick a generic burger or pizza. I wanted to build something tied directly to home and my culture: Ilish Polao (Hilsha fish cooked with fragrant rice). Hilsha is the national fish of Bangladesh, and Ilish Polao—paired with a side of spicy-sweet tomato chutney—is the ultimate comfort meal in our house. Translating a dish loaded with personal memory into raw CSS felt like the perfect way to combine culture with code. Demo mahbubasultanaety.github.io GitHub Repository: MahbubaSultanaEty / hilsha-polao How I Built It Instead of relying on SVGs or background images, every visual element in this piece is built from scratch with HTML elements and pure CSS styling. Here is a quick breakdown of what went into the scene: Fish-Shaped Platter: Built using layered border-radius curves and subtle box-shadows to mimic ceramic depth. The Polao Mound: Formed using rounded CSS containers with layered gradient textures. Scattered Rice Grains: Instead of hardcoding dozens of tags in HTML, I used a tiny JS script to generate and randomly position rice grains over the mound so the texture feels natural rather than grid-like. The Hilsha Piece: Crafted with CSS clip-paths and custom border geometries to get the signature cut and inner texture right. Animated Steam: CSS keyframe animations controlling opacity and vertical translate transforms to give the food a hot, fresh feel. Garnishes & Sides: Added cinnamon sticks, bay leaves, green chilies, and a small side bowl of tomato chutney to complete the plate. The Sprinkle of Javascript: Rice Generation Hardcoding hundreds of rice grains in static HTML felt redundant. So I used the minimal for loop JS approach to scatter them: This tiny bit of scripting saved me time and made the plate look organic every single render. Takeaways Building CSS art always forces you to think dif

Lexus' latest luxury sedan is priced right and drives great, but feels like it's built around outdated EV tech.

I have 312 docs in my personal knowledge DB. Tweets, arxiv abstracts, Zenn articles, blog posts, YouTube transcripts. Claude Code writes to it, reads from it, and cites out of it every day. That number is not a brag. It is the reason I finally have data on which retrieval strategy holds up in an LLM-native workflow. I tried four. The one I ship is the one I tried last and expected to lose. Three of the four broke in ways that are worth naming, because the broken versions are what most tutorials will tell you to build. The setup, so we agree on what got benchmarked The knowledge DB is called context-forge internally. It is a folder, some markdown files, and a SQLite table. Claude Code adds to it via CLI, searches via CLI, and reads the underlying markdown directly when it needs the full text. It took eight hours to build the CLI, three months to accumulate the 312 documents at a pace of one to five per day, and about 15 minutes a day of my time to keep it flowing. Each doc has metadata: source URL, a credibility score 1-5, one to three categories, a short summary. The autoregistration pipeline is Claude Code itself: I paste a URL, it fetches, summarizes, scores, categorizes, writes the markdown, commits, and updates the SQLite index. The pipeline is not the interesting part. The retrieval strategy is. I ran each of the four strategies for two weeks against the same day-to-day tasks: writing a chapter, answering "what did that person say about X," and building an argument for a decision. Same me, same DB, different retriever. Layer 1: pure semantic RAG (vector embeddings). Broke at 200 docs The first version was the textbook answer. Embed every document with a sentence transformer, store the vectors in SQLite with a similarity index, retrieve the top-k on every query. This is the pattern Silicon Slopes covers for code-level RAG and Anthropic itself has an issue open for a built-in version . It worked at 50 docs. It worked at 100. Around 200 documents it started retrie

Every invoicing tool I tried wanted an account, a subscription, and a copy of my client list on its servers — then charged me monthly to put my own logo on my own invoice. So I built the opposite. Billfold is a complete invoice generator that runs entirely in your browser. No account, no backend, no build step. The whole app is a single index.html file you could email to yourself. It's MIT-licensed and the source is right here: github.com/quantum-hacker0/billfold . Here are the three parts that were actually fun to build. 1. "No server" isn't a privacy policy — it's the architecture The usual pitch is "we take your privacy seriously." That's a promise you have to trust. I wanted it to be a fact you can verify : Open DevTools → Network, create an invoice, and count the requests. It's zero. There's nothing to upload because there's nowhere to upload it. Data lives in localStorage . The app is HTML/CSS/JS inlined into one file — no framework, no bundler, no node_modules . Download it once and it works offline forever. 2. Sharing an invoice without a database — put it in the URL hash This was the interesting constraint. How do you send someone a view-only invoice when you have no server to store it on? The trick: encode the whole document into the URL hash fragment . The fragment (everything after # ) is the one part of a URL that browsers never send to the server — it stays client-side. function shareLink ( state ) { const json = JSON . stringify ( state ); const encoded = btoa ( unescape ( encodeURIComponent ( json ))) . replace ( / \+ /g , ' - ' ). replace ( / \/ /g , ' _ ' ). replace ( /=+$/ , '' ); // base64url return location . origin + location . pathname + ' #v= ' + encoded ; } The recipient's browser reads the fragment, decodes it, and renders the invoice locally. The data rides inside the link and never touches a host — not even mine. PDF export, by the way, is just window.print() with a print stylesheet. 3. Invoices as URLs — with an npm package Because the a

Most companies we work with don't have a data inventory. When we ask "where's your data listed?" (where it lives, what it contains, who owns it), the answer is usually some version of "we don't have one." No comprehensive map of data locations. No business impact assessment for different data types. Unclear ownership and accountability. You can't protect what you haven't mapped. And you can't make good decisions about backup strategy when you don't know what you're backing up. Data Has a Half-Life Not all data ages the same way. Some data becomes stale quickly. If you're aggregating information from external sources like market data, business intelligence, or operational metrics, the value is often in the freshness. Yesterday's data might be useful for trends, but it's not the crown jewels. Source data and processed insights need different protection levels. The raw inputs you collect might be recreatable from upstream sources. The analysis and transformations you've built on top might take significant effort to reconstruct, or might be regenerated in hours if you have the pipeline intact. This changes the backup math. If your data pipeline gets destroyed but you can pull from upstream sources and recreate everything within an acceptable timeframe, maybe you don't need to back up the work product at all. Maybe you just need to protect the source data and the pipeline itself. Understanding your data's half-life helps you spend backup dollars where they actually matter. The Cost vs. Risk Conversation Backup costs can reach hundreds of thousands of dollars annually. Cross-region replication, long-term retention, disaster recovery infrastructure. It adds up fast. That's money not going to engineers or product development. A real tradeoff. The question is: what's the actual business impact if this data disappears? What's the downtime cost? What's your real risk tolerance? These are executive decisions, not just technical ones. They require someone to say "we're willing t

Vista previa técnica: Iter todavía no está publicado en PyPI y no existe un paquete oficial instalable. Abrir un recurso, convertir datos o cambiar de backend suele exigir aprender una interfaz diferente y repetir código de integración. Iter nace de una idea sencilla: Aprende una vez. Usa cualquier biblioteca. iter convert data.json to data.csv El usuario expresa una sola intención. Iter se encarga de abrir el recurso, detectar los formatos, seleccionar un adaptador compatible, convertir los datos y guardar el resultado. Una intención. Una instrucción. ¿Qué busca cambiar Iter? Actualmente, una tarea sencilla puede exigir: importar bibliotecas; aprender APIs diferentes; configurar formatos manualmente; escribir código de integración; seleccionar cada backend. Con Iter, el usuario indica principalmente qué quiere conseguir: iter analyze sales.csv Iter selecciona automáticamente una herramienta compatible. Si el usuario necesita controlar la biblioteca, puede indicarla: iter analyze sales.csv with pandas La automatización es el comportamiento predeterminado. El control detallado sigue siendo opcional. Everything is a Resource Iter representa archivos, datos y recursos web mediante una estructura común llamada Resource . El sistema está organizado alrededor de cinco componentes: Resource : representa el recurso. Resolver : identifica formatos, tipos y backends. Registry : registra y selecciona adaptadores. Adapter : ejecuta operaciones concretas. Engine : coordina el proceso. La meta no es afirmar que todas las bibliotecas son idénticas. La meta es unificar intenciones comunes y conservar las diferencias importantes cuando sean necesarias. Estado actual Iter 0.3.0-rc.2 está en fase de corrección de errores y validación privada. Actualmente: el código principal permanece privado; Iter todavía no está publicado en PyPI; no existe un paquete demostrativo; la sintaxis puede ajustarse antes del lanzamiento; solamente se anunciarán como disponibles las funciones implementadas

Welcome to Part 2 of the JS interview series! This time we're tackling functions, scope, and the topic that trips up even experienced developers in interviews: closures . Missed Part 1? Check out Fundamentals & Data Types first. Q1. What is a closure? A closure is what happens when an inner function "remembers" and continues to have access to the variables from its enclosing (outer) function's scope, even after that outer function has already finished running and would normally have had its local variables cleaned up. This works because JavaScript functions don't just capture the values of outer variables — they capture live references to them, keeping the entire surrounding scope alive in memory for as long as the inner function itself is reachable. Closures are one of the most powerful and commonly used patterns in JavaScript. They're the mechanism behind data privacy (since variables inside a closure can't be accessed from outside except through the functions that were given access), factory functions that generate customized functions, memoization caches, and event handler callbacks that need to remember state from when they were created. In the classic counter example below, each call to counter() creates a fresh, independent count variable that only the returned function can see or modify — there's no way to reach into it from outside. function counter () { let count = 0 ; return () => ++ count ; } const inc = counter (); inc (); // 1 inc (); // 2 Q2. What is lexical scoping? Lexical scoping (also called static scoping) means that a variable's accessibility is determined entirely by where it's physically written in your source code — not by which function called which, or the order in which functions happen to execute at runtime. When JavaScript compiles your code, it can already determine, just by looking at the nesting of functions and blocks, exactly which variables any given piece of code will be able to see. This is what allows an inner function to "reach

Software projects fail on fixed-price contracts. This is not a controversial statement — the Standish Group's CHAOS report has tracked this for decades, showing that only 31% of software projects succeed on time and on budget, while 50% are challenged and 19% fail outright. But the conventional wisdom about why they fail — scope creep — misses the real problem. Scope creep is a symptom. The real disease is specification ambiguity . The Map Is Not the Territory Paweł Brodziński, an experienced software delivery leader, captured this perfectly with a simple analogy. A specification is a map of the software you want to build. And as with any map, its representation of the terrain is necessarily imperfect. For a perfect map, it would have to be as large as the terrain itself. "The only absolutely precise specification of a software project is the code itself. But if you already have that, why would you buy it?" When you write "As a workspace owner, I can set administrative privileges to workspace members," two people reading that sentence will envision different things. One imagines a simple dropdown with three permission levels. The other imagines role-based access control with custom policies, audit logs, and delegation. Both are reasonable interpretations of the same text. The PMI's research on communications complexity confirms why this happens: the number of communication paths grows geometrically with project size ( n(n-1)/2 ), and every path is a channel where ambiguity can creep in. Even a simple conversation involves encoding, decoding, and filtering — two receivers can interpret the same message differently. Why This Is Not Scope Creep Scope creep is when a client asks for something new after the contract is signed. That's a well-understood problem with well-understood countermeasures: change requests, sign-offs, contingency buffers. Specification ambiguity is different. It's not about adding new things — it's about both parties believing they agreed on the sa

Every software agency has been here: the client asks for a price, you give a range (say $45k–$65k), and two things can happen. Either the client nods and you win the deal at the low end — or they get suspicious and ask "so you don't actually know how much it costs?" Range pricing is often misunderstood. Used wrong, it looks like you're guessing. Used right, it's the most honest and professional way to price software projects — because anyone who gives you a single fixed number for an undefined project is either padding heavily or gambling with their margin. This guide covers when to use range pricing, how to structure it, and — most importantly — how to present it so clients trust you more, not less. Why Single-Point Pricing Is a Problem A fixed price for an undefined project forces you into one of two positions: You pad aggressively — add 40% contingency, quote $70k for a project you'd happily do for $50k. If the scope doesn't expand, the client overpays. If it does, you're protected. Either way, one party loses. You guess lean — quote $50k based on your best assumptions. If the client adds features mid-project, your margin evaporates. The client thinks they're paying for X, you're building X+Y. Both parties end up frustrated. A pricing range avoids both traps. It says: "based on what we know today, this project falls between $45k and $65k. Here's what needs to be true for the low end, and here's what would push it toward the high end." That's not guesswork. That's transparency. The Anatomy of a Good Pricing Range Not all ranges are created equal. A useful range has three properties: 1. Width That Respects Uncertainty The width of your range communicates how well you understand the project. Range width What it signals When it's appropriate < 15% ($50k–$57k) High confidence Detailed spec, similar past projects, known team 15–30% ($50k–$65k) Moderate confidence Clear brief, some unknowns in tech or integration 30–50% ($50k–$75k) Low confidence Vague brief, new domain

Platform engineering maturity is emerging as an important factor in determining whether organizations can turn AI adoption into sustainable operational value, according to Perforce Software's 2026 Platform Engineering Report. By Craig Risi

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This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry. Did anyone ask for...

Hi, I’m Hélène. I’ve had computers in my life for more than forty years now, which still surprises me when I say it out loud. I started out as an eight-year-old kid playing simple games on a family computer, before the NES, before “PC gaming” was really a thing. We loaded games from cassette tapes, listened to modems sing their weird little songs, and waited for desktop machines to slowly grind their way through a boot sequence. I taught myself to program as a teenager because I wanted to make the computer do more than just play those games. Later, I went through technical school, then university, and graduated with a Computer Science degree. I did a Master-level short program in project management. I worked as a software developer for years, and now I lead a team. Along the way I read piles of books, watched improv and theatre, devoured Choose Your Own Adventure stories — only to realize much later that all of that was quiet leadership training in disguise. But there was one book I never found: the one that explained how to grow from junior to a trusted, impactful developer in a way that felt honest and practical. Not just “write clean code” or “communicate better,” but how to actually do those things, day after day, with real people, real constraints, and real doubts in your head. When I started my career, there were textbooks on algorithms and operating systems. There were tutorials on whatever language was hot that year. There were business books full of buzzwords. What I couldn’t find was the in-between book: something written by a practicing software developer, talking to another developer, about the messy, human parts of this job. Junior to Engineer is my attempt to write that missing book. Who this book is for If you’re a junior or intermediate software developer and you’re wondering things like: “How do I become the person people trust with the hard problems?” “What should I actually focus on in the first 5–10 years of my career?” “Why does everyone else se

Bilibili's 412 Incident, Explained: How v1.5.0 Absorbed It In June 2026, Bilibili quietly began rejecting yt-dlp with HTTP 412 errors. Agents wired to scrape it broke — except the ones sitting behind Agent-Reach, which rerouted the channel before most developers noticed. Agent-Reach is a local, MIT-licensed capability layer that gives shell-capable coding agents live internet access by selecting and routing to upstream CLIs rather than proxying data itself . When Bilibili started 412-blocking yt-dlp in June 2026, v1.5.0 rerouted the Bilibili channel to bili-cli with zero user action, while YouTube kept using yt-dlp untouched . The fix landed centrally: the maintainer reordered backends, so no individual builder had to patch a private integration. Quick Answer: When Bilibili began returning HTTP 412 to yt-dlp in June 2026, Agent-Reach v1.5.0 automatically rerouted its Bilibili channel to bili-cli — agents kept working with no user action. The release passed 32 end-to-end tests across 13 channels and grew its suite from 107 to 162 tests. The framing shift matters: v1.5.0 describes itself as a capability layer, not a tool collection. Each platform gets an ordered primary-plus-fallback backend list; after setup, your agent calls those CLIs directly and Agent-Reach never sits in the data path . The June 11, 2026 release passed 32 end-to-end tests across 13 channels and grew its test suite from 107 to 162 tests . Platform Primary backend Fallback Web pages Jina Reader — YouTube yt-dlp — GitHub gh CLI — RSS feedparser — Bilibili bili-cli OpenCLI (subtitles) Twitter/X twitter-cli OpenCLI Reddit OpenCLI rdt-cli XiaoHongShu OpenCLI xhs-cli LinkedIn linkedin-mcp Jina Reader Global search Exa via mcporter — "capability layer: multi-backend routing + real doctor + OpenCLI" — Agent-Reach v1.5.0 release framing (source: Agent-Reach CLAUDE.md ). The behavior is easy to model. The following minimal snippet — which was executed and returns exit 0 — illustrates the "absorb and keep wo