How YouTube achieves instant loading with YouTube's DevTools

💻 It all started with a simple frustration... Every time I worked with APIs, I’d end up copying messy JSON into random online formatters — Some were slow, others spammed me with ads, and a few even sent data to their servers. One day, while debugging a client’s API, I thought — “Why am I trusting sensitive data to some random site?” That’s when I decided to build my own solution. 🔥 JSON Formatter Online — a free, privacy-friendly, and super-fast JSON formatter built for developers who value speed and simplicity. ⚡ Instantly formats and validates JSON 🔒 Runs 100% in your browser (no uploads!) 🧩 Clean, ad-free UI 🌗 Dark mode for late-night debugging I didn’t plan to launch it publicly at first—it was just a side project to make my own workflow faster. But when I shared it with a few dev friends… they started using it daily. Now it’s live for everyone. → https://lnkd.in/geiMP6qy Here’s what it looks like 👇 (attach your screenshot image here) Next up, I’m planning: JSON → CSV converter Shareable links Auto error detection Sometimes the best tools are born out of personal pain. Would love your thoughts — what’s one tool you wish existed? 💬 #webdevelopment #javascript #frontend #developers #json #productivity #opensource #webtools #devcommunity #webdev #jsonformatter

🚀 What if Promise.all(), .map(), and for-await-of had a baby? 👉 Read the full story: https://lnkd.in/dkmmS6Vt Meet Array.fromAsync() — the new JavaScript superpower that makes async data handling clean, declarative, and effortless. No more juggling between loops, maps, or promise chains — just one beautiful one-liner: ```Example``` const users = await Array.fromAsync(ids, fetchUser); `````` ✨ It’s like: - Promise.all() — because it runs async tasks in parallel - .map() — because it transforms each element - for-await-of — because it handles async iterables All rolled into one ergonomic API. 💫 🧠 In my latest article, I dive deep into: - Real-world use cases - Async generator magic Why this small feature changes how we think about async in JavaScript 👉 Read the full story: https://lnkd.in/dkmmS6Vt #JavaScript #ES2023 #WebDevelopment #Frontend #AsyncProgramming #CodingTips #WebTechJournals #LearningMindset #ContinuesGrowth #FrontendDevelopment #PublicisSapient #PublicisGroupe

If this post found you, take it as your sign to build something small this week. You don’t need a perfect idea or a big plan. What matters is getting started with a stack you can set up quickly. How I’d start a side project in the end of 2025: - Pick a problem you actually have - Cut the scope to what fits in 10 days - Use tools you already know - Build one vertical slice end to end - Ship it publicly Two simple paths: 💡 Frontend-only (fastest to ship) - Vite + React - Tailwind or plain CSS - Local JSON or MockAPI - Deploy on Vercel or Netlify ⚙️ Full-stack (when you need auth or data) - Next.js (App Router) - Auth.js or Clerk - Drizzle ORM + Postgres (Neon or Supabase) - Deploy on Vercel, add Cron if needed First milestone ideas: - One item added and saved - One full flow works end to end - One clear result displayed - App live and working The goal isn’t perfection. The goal is to finish something real you can click, test, or share by next week. 👉 What would you build if you gave yourself 10 focused days? #webdev #fullstack #frontend #sideproject #softwareengineering

I build a simple JSON Viewer and here's how it can help you. Many devs complain that they don't have a simple JSON viewer tool that can show them how their data is structured. I got tired of that too. Why I built this: Every developer I know (including me) deals with JSON daily. But we're all using random websites that: ❌ Send our data who-knows-where ❌ Have terrible UX ❌ Crash on large files So I built something just for that but better → https://lnkd.in/d8K7j3BT What it does: Paste messy JSON → Click Parse → Get beautiful formatted output → Copy it That's literally it. No ads, no tracking, nothing. If the data is missing a comma or } somewhere, it will return an error telling you the line so you can quickly adjust My solution runs 100% in your browser or you can use my live github page and your data never leaves your machine. Tech I used: React (because components) CSS3 animations (design focused 🌊 easy on the eyes) GitHub Pages (lite, simple and free hosting FTW - every developer knows it) The best part? I kept it simple. No feature creep. No "enterprise" bloat. Just one tool that does one thing really, really well. Try it → https://lnkd.in/d8K7j3BT Question for you: What's the most annoying dev tool you use regularly? Drop it below - maybe I'll build a better version 👇 P.S. It's open source. Star it, fork it, roast my code - I'm here for all of it 😄 #WebDevelopment #React #JavaScript #DevTools #BuildInPublic

I just shipped a major upgrade to react-snap-state and it changes everything Last week I released react-snap-state, a key-based state management library built on useSyncExternalStore. Since then, I have been refining the internals and rethinking the API design. Today’s update brings two major upgrades and one important architectural shift: 🚀 New in this release 1. useDeriveValue A lightweight way to compute derived state from one or more store keys with automatic subscriptions and comparator support. 2. Async setter Async state updates are now first-class. You can show a placeholder instantly, run your async work, and have the final value update the store automatically. 🧠 What I redesigned Comparators now live only on reads, not writes. This follows a simple philosophy: 𝐖𝐫𝐢𝐭𝐞𝐬 𝐬𝐡𝐨𝐮𝐥𝐝 𝐛𝐞 𝐝𝐮𝐦𝐛. 𝐑𝐞𝐚𝐝𝐬 𝐬𝐡𝐨𝐮𝐥𝐝 𝐛𝐞 𝐬𝐦𝐚𝐫𝐭. This makes behavior fully predictable and eliminates hidden complexity inside setters. Why this matters? react-snap-state now feels even closer to how React wants you to manage state: - isolated subscriptions - no context re-renders - concurrent-safe - minimal API If you're curious and want a tiny alternative to RTK/Zustand/Jotai for key-based state, check it out: 👉 npm: https://lnkd.in/dBwrGcmk 👉 GitHub: https://lnkd.in/dF7HqVTr Excited to keep improving this. Helps me learn a lot about react internals and state management. #ReactJS #JavaScript #TypeScript #OpenSource #WebDev

💡 React Tip of the Day! Ever faced this? 👇 Your child component triggers an API call, but you want to re-fetch the data after the parent completes some task — without moving all that logic up to the parent 😩 Here’s a simple, elegant trick 💫 Use the key prop to re-render the child! <ChildComponent key={refreshKey} /> Then in the parent: setRefreshKey(prev => prev + 1); 💥 Each time the key changes, React remounts the child component — triggering its useEffect (and your API call) again automatically. Why this rocks 🚀 ✅ No need to uplift or duplicate API logic ✅ Keeps child components self-contained ✅ Clean, predictable, and easy to manage A neat little trick to refresh data without refactoring half your tree! 😄 #ReactJS #WebDev #FrontendTips #CleanCode #ReactHooks

🚀 𝐒𝐭𝐨𝐩 𝐑𝐞-𝐫𝐞𝐧𝐝𝐞𝐫𝐢𝐧𝐠 𝐄𝐯𝐞𝐫𝐲𝐭𝐡𝐢𝐧𝐠: 𝐀 𝐑𝐞𝐚𝐥-𝐖𝐨𝐫𝐥𝐝 𝐂𝐚𝐬𝐞 𝐟𝐨𝐫 𝐮𝐬𝐞𝐂𝐚𝐥𝐥𝐛𝐚𝐜𝐤 & 𝐑𝐞𝐚𝐜𝐭.𝐦𝐞𝐦𝐨 Most devs skip 𝐮𝐬𝐞𝐂𝐚𝐥𝐥𝐛𝐚𝐜𝐤 and 𝐑𝐞𝐚𝐜𝐭.𝐦𝐞𝐦𝐨 - not because they don’t care about performance…but because they don’t realize where they actually make an impact. But here's a production scenario that changed my mind: 𝐓𝐡𝐞 𝐏𝐫𝐨𝐛𝐥𝐞𝐦: Imagine a dashboard with a data table showing 𝟏,𝟎𝟎𝟎+ 𝐫𝐨𝐰𝐬. Each row has an "Edit" button. Without optimization, every keystroke in a search filter re-renders ALL 𝟏,𝟎𝟎𝟎+ 𝐫𝐨𝐰𝐬 - even though only the filtered results changed. Every time searchTerm updates, handleEdit is recreated, forcing ALL 𝟏,𝟎𝟎𝟎+ 𝐫𝐨𝐰𝐬 UserRow components to re-render. ✅ 𝐓𝐇𝐄 𝐅𝐈𝐗: See the Snapshot 𝐓𝐡𝐞 𝐈𝐦𝐩𝐚𝐜𝐭: 𝐁𝐞𝐟𝐨𝐫𝐞: 1,000+ re-renders per keystroke = ~250ms lag 𝐀𝐟𝐭𝐞𝐫: Only visible rows re-render = <16ms (60fps) 𝐔𝐬𝐞𝐫 𝐄𝐱𝐩𝐞𝐫𝐢𝐞𝐧𝐜𝐞: Smooth, responsive filtering 𝐖𝐡𝐞𝐧 𝐭𝐨 𝐔𝐬𝐞 𝐢𝐧 𝐏𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐨𝐧: 𝐋𝐚𝐫𝐠𝐞 𝐋𝐢𝐬𝐭𝐬/𝐓𝐚𝐛𝐥𝐞𝐬 - Any component rendering 50+ items 𝐂𝐨𝐦𝐩𝐥𝐞𝐱 𝐂𝐡𝐢𝐥𝐝𝐫𝐞𝐧 - Components with expensive calculations or deep trees 𝐅𝐫𝐞𝐪𝐮𝐞𝐧𝐭 𝐏𝐚𝐫𝐞𝐧𝐭 𝐔𝐩𝐝𝐚𝐭𝐞𝐬 - Forms, filters, real-time data 𝐄𝐯𝐞𝐧𝐭 𝐇𝐚𝐧𝐝𝐥𝐞𝐫𝐬 𝐚𝐬 𝐏𝐫𝐨𝐩𝐬 - Especially with memo'd children So next time your React app feels sluggish, don’t just look at network calls. 👉 Check your re-renders. 👉 Add memoization where it matters. That’s the difference between “𝐢𝐭 𝐰𝐨𝐫𝐤𝐬” and “𝐢𝐭 𝐬𝐜𝐚𝐥𝐞𝐬.” 💪 #React #WebPerformance #JavaScript #Frontend #SoftwareEngineering

💭 I’ll just wrap it in useMemo - that’ll make it faster! That was me, a few months ago. I wanted to optimize a component that was rendering a big list, so I memoized everything. Then I opened React Profiler...and saw worse performance. 🤦♂️ 🧠 What Happened? useMemo doesn’t make code magically faster. It caches a computed value - but that caching itself comes with a cost. If the calculation is cheap or runs often, React ends up: Spending extra time checking dependencies Allocating memory to store cached values And sometimes re-running the memoized function anyway So instead of improving performance, it actually slowed down re-renders. ✅ The Fix (and Rule of Thumb) Use useMemo only when: The computation is expensive (sorting large data, complex transformations) The dependencies change infrequently Otherwise, just compute inline. React is fast enough for most cases. Example: // ❌ Over-optimization const doubled = useMemo(() => numbers.map(n => n * 2), [numbers]); // ✅ Simpler & often faster const doubled = numbers.map(n => n * 2); 💡 Takeaway Every optimization has a cost. Don’t reach for useMemo - measure first, optimize later. 🗣️ Your Turn Be honest - have you ever overused useMemo (or useCallback) thinking it’d boost performance? How do you decide when it’s actually worth it? #ReactJS #Performance #WebDevelopment #ReactHooks #FrontendDevelopment #JavaScript #CleanCode #Optimization #DevCommunity

Today, I explored how to make websites more interactive and data-driven by integrating external APIs. Instead of relying on static content, I learned how to fetch and display real-time data — adding depth and functionality to the web experience. 🔹 Objective: Integrate external data sources to provide dynamic, real-time content. 🔹 Key Steps: 1️⃣ Selected a public API (like JSONPlaceholder) and explored its endpoints. 2️⃣ Used the fetch() function in script.js to retrieve data asynchronously. 3️⃣ Parsed the JSON response and dynamically updated the DOM to show live content. 💡 Takeaway: APIs unlock endless possibilities — from fetching user data to displaying live updates. This exercise deepened my understanding of asynchronous JavaScript and real-world data handling. #CognifyzTechnologies #WebDevelopment #JavaScript #APIIntegration #FrontendDevelopment #LearningByDoing #CodingJourney

🎯 JavaScript Sorting Algorithms Cheat Sheet ✅ Bubble sort ✅ Selection sort ✅ Insertion sort ✅ Merge sort ✅ Quick sort ✅ Heap sort ✅ Counting sort ✅ Radix sort ✅ Bucket sort ✅ Shell sort Save & share with your team! The Complete Dev Roadmap with SaaS Boilerplate ➡️ https://champ.ly/-FLdfic_ --- If you found this guide helpful, follow TheDevSpace for more tips, tutorials, and cheat sheets on web development. Let's stay connected! 🚀 Also follow 👉 W3Schools.com & JavaScript Mastery to learn web development. #JavaScript #Sorting #Algorithms #Interview #WebDevelopment #CheatSheet #Frontend #Coding