Node.js Internals Explained: Process Start to Event Loop

Today Class was on Internals of Node.js! Understood how Node.js runs on a single main thread, uses the event loop to handle async tasks, and a thread pool (default 4 threads) for heavy operations. Also learned how phases like I/O polling, expired callbacks, and setImmediate work behind the scenes. Really interesting to see how Node.js executes code internally. #NodeJS #NodeJSInternals #JavaScript #EventLoop #ChaiCohort26 #Chaicode Hitesh Choudhary Chai Code #piyushgarg Anirudh Jwala Akash Kadlag Jay Kadlag JavaScript

🚀 What I Learned Today: Node.js Internals • Node.js runs JavaScript on a single main thread • Top-level code executes first before the event loop starts • Import statements load during initialization • Event Loop manages asynchronous operations Event Loop Phases: • Timers → setTimeout() / setInterval() • I/O Polling → file system & network operations • Check → setImmediate() (Node.js specific) • Close Callbacks → cleanup tasks • Node.js uses a libuv worker thread pool (default: 4 threads) • Thread pool size can be changed using process.env.UV_THREADPOOL_SIZE https://lnkd.in/gwFG5WVW thank you Piyush Garg sir Hitesh Choudhary sir Akash Kadlag sir #chaiaurcode #NodeJS #JavaScript #Backend #EventLoop

While working on a full-stack project with Next.js, I sometimes needed to quickly check environment variables without modifying the code. Here’s a simple way to do it directly from the terminal (required 'dotenv' library): Check env value: node -e "require('dotenv').config(); console.log(process.env.DATABASE_URL)" It’s a small tip, but quite useful when you want to check env value. I’ll probably share a few more small things like this from my project along the way. #nextjs #nodejs #dotenv #webdevelopment #softwareengineering #buildinpublic #javascript #devtips #webdevUK

Day 81 / 365 👨💻 Recap of recent React tooling sessions. ⚙️ How @vitejs/plugin-react works ⚡ Role of esbuild and Babel (Fast Refresh) 📦 Rollup for production builds 🔢 Version symbols in package.json 📤 Named vs default exports #365DaysOfCode #React #JavaScript #Frontend

React Query changed how I think about state — and I have not used Redux since The server state vs client state distinction that React Query makes explicit replaced my need for Redux entirely. Here is the mental model shift. Full breakdown (7 min read) → https://lnkd.in/gcUhHrV2 #ReactJS #Frontend #JavaScript #TypeScript #WebDev #UIEngineering

💡Difference Between State and Props in React 👉 Props → Passed from parent to child (read-only) 👉 State → Managed inside the component (mutable) Simple rule I follow : Props = external data State = internal data Understanding this made React much clearer for me 👆 #reactjs #javascript #frontenddeveloper #webdevelopment

Many developers keep switching between React, Vue, Angular, and new tools… But without strong fundamentals, everything feels confusing. Focus on: • JavaScript core concepts • DOM & browser behavior • Logic & problem solving • CSS fundamentals Once your basics are strong, you can learn any framework easily. 💡 Don’t chase tools — master the foundation. What do you focus on more? 👇 Fundamentals or frameworks? #WebDevelopment #JavaScript #ProgrammingBasics #FrontendDeveloper #DeveloperTips #CodingJourney #LearnToCode #BuildInPublic

Day 75 / 365 👨💻 Continued learning React. 📘 Learned why React.createElement can be inconvenient ✨ Introduction to JSX ⚙️ Understood the role of Babel 🧩 How JSX works under the hood 🧠 Creating basic React components 🔢 Using JavaScript expressions inside JSX #365DaysOfCode #React #JavaScript #Frontend

Day 82 / 365 👨💻 Started understanding React state. 🧠 Problem that useState solves ⚙️ How useState works step by step 🔄 Why re-rendering happens ⏳ Why state updates aren’t immediate 🔁 Updater function vs direct value #365DaysOfCode #React #JavaScript #Frontend

Day 80 / 365 👨💻 Continued learning React tooling. 📦 Role of Rollup in production bundling 🔢 Understood version symbols (^, ~) in package.json 📤 Named vs default exports 📄 Why JSX files use .jsx extension #365DaysOfCode #React #JavaScript #Frontend