Node.js Modules Explained

I struggled with this React concept more than I expected… 👇 👉 Why are my API calls running twice? ⚙️ What you’ll notice You open your network tab and suddenly see this: api/me → called twice api/roles → called twice api/permissions → called twice Just like in the screenshot 👇 Same request, duplicated… again and again. ⚙️ What’s actually happening In React (development mode), if your app is wrapped in Strict Mode, React will run effects twice on purpose. useEffect(() => { fetch("/api/users") .then(res => res.json()) .then(setUsers); }, []); Even though it looks like it should run once… it doesn’t (in dev). 🧠 What’s going on under the hood React basically does a quick cycle: mount → unmount → remount Why? To catch hidden side effects To check if cleanup is handled properly To make sure your logic doesn’t break on re-renders So if your API call runs twice, React is just making sure your code can handle it. 💡 The important part This only happens in development Production behaves normally (runs once) Your side effects should be safe to run multiple times 🚀 Final thought If your network tab looks “noisy” like the screenshot, it’s not React being broken — it’s React being careful. And once you understand this, debugging becomes a lot less confusing. #React #Frontend #JavaScript #WebDevelopment #ReactJS #SoftwareEngineering

Every Node.js app eventually hits "I need rate limiting." You Google it. You find express-rate-limit. You install it. Then you realize: → It only works with Express → You also have a Next.js Edge route → And a React frontend making too many API calls → Oh, and you need Redis for production So now you're stitching 4 different libraries together. 😅 That's exactly why I built limiterx. One package. Every runtime. ✅ Express, Koa, Node HTTP ✅ Next.js API routes + Edge Middleware ✅ React hook for client-side throttling ✅ Fetch + Axios wrappers ✅ Redis store out of the box ✅ 3 algorithms: fixed-window, sliding-window, token-bucket And it ships with zero runtime dependencies. Tree-shakeable. TypeScript-first. Works on Node, browsers, Edge, and Bun. Getting started is literally this: npm install limiterx Then: app.use(rateLimitExpress({ max: 100, window: '15m' })) That's it. If you're building anything in JS/TS that talks to an API — this is for you. 🔗 npm: https://lnkd.in/gxbf3Jxt 🐙 GitHub: https://lnkd.in/gxt-RAi3 Drop a ⭐ if this saves you a headache. And share with anyone building Node apps — they'll thank you. #nodejs #javascript #typescript #webdev #opensource #ratelimiting #nextjs #developer

For a few days, I was working on building a sticky Notes App using Node.js and Express.js, and instead of using plain HTML, I experimented with EJS (Embedded JavaScript templates). While doing that, I noticed some interesting differences between using static HTML and server-side templating with EJS: • With HTML, everything is static and separate • With EJS, I can dynamically render data directly from the backend • Passing variables from Express to views makes the app feel more “real-time” and flexible • Folder structure becomes more organized when separating routes, views, and logic • It feels closer to how real-world backend-driven applications work This project enhanced my understanding of how frontend and backend integrate more seamlessly through the use of templating engines. I would love to hear how others approach structuring Node.js + Express projects with EJS, and if there are any improvements or best practices you would recommend to make this setup more efficient or scalable. #Nodejs #Expressjs #EJS #BackendDevelopment #WebDevelopment #LearningByDoing

By default, React is fast. But as data grows, unnecessary re-renders quietly kill performance. Today I learned two hooks that every serious React developer needs to know: 🗒️ useMemo — A cache for heavy calculations. Instead of re-running expensive logic on every render, React stores the result and reuses it. Think of it like a sticky note your genius friend writes so they don't have to solve the same problem twice. 🔗 useCallback — Stabilizes your functions. In JS, functions are objects — so a "new" one gets created on every render. This hook keeps the reference the same, stopping child components from re-rendering for no reason. The senior wisdom I picked up today? Don't over-optimize. These hooks cost memory. Only reach for them when you actually see a lag — not before. Understanding when to optimize is what separates professional developers from the rest. Tomorrow: I'm building my own tools with Custom React Hooks! 👀 Question for you: Do you optimize as you go, or wait until something feels slow? Drop your strategy below 👇 #CodeWithWajid #ReactJS #WebDevelopment #100DaysOfCode #LearningToCode #BuildingInPublic #ReactOptimization #WebPerf

🚀 Ever wondered how those tiny square boxes (QR codes) magically open websites in seconds? 🤔 So here’s something interesting… Instead of using online generators, I tried building my own QR Code Generator using Node.js 💻⚡ And guess what? It’s surprisingly simple once you break it down 👇 👉 You give a URL 👉 The program processes it 👉 Boom! A scannable QR code image is generated instantly 📱 No fancy setup. No heavy tools. Just pure JavaScript + Node.js doing its magic ✨ 💡 What makes this cool? We use QR codes almost every day — payments, logins, sharing links — but rarely think about how they’re created behind the scenes. Building one gives a whole new perspective 🔍 ⚙️ The fun part: Working with Node.js packages makes it super easy to convert real-world ideas into working tools. This is where development starts feeling practical, not just theoretical. 🔥 This is the kind of stuff that reminds me: Small projects = Big clarity Thinking of taking this further by turning it into a simple web app with custom designs 🎨 If you’ve ever thought Node.js is just for backend APIs… try something like this 😉 #NodeJS #JavaScript #CodingJourney #BuildInPublic #Developers #TechLife #LearningByDoing

26 questions. The difference between knowing React on paper and surviving a real production codebase. Here are the 26 questions categorized by the depth of experience required: Level 1: The Foundations => How does React’s rendering process work? => What’s the difference between state and props? => What are hooks, and why were they introduced? => What are controlled vs uncontrolled components? => When would you use refs? => How do you handle forms and validations? Level 2: State & Logic => When should you lift state up? => How do you manage complex state in an application? => When would you use useState vs useReducer? => How do useEffect dependencies work? => How do you handle API calls (loading, error, success states)? => How do you manage shared state across components? => Context API vs Redux — when would you use each? Level 3: Performance & Scale => What causes unnecessary re-renders, and how do you prevent them? => What is memoization in React? => When would you use React.memo, useMemo, and useCallback? => How do you structure a scalable React application? => How do you optimize performance in large-scale apps? => What tools do you use to debug performance issues? => How do you secure a React application? => How do you test React components effectively? Level 4: The War Stories => Have you faced an infinite re-render issue? How did you fix it? => Tell me about a complex UI you built recently. => How did you improve performance in a React app? => What’s the hardest bug you’ve fixed in React? => How do you handle 50+ inputs in a single form without lag? Syntax is easy to Google. Deep understanding is hard to fake. #ReactJS #FrontendDevelopment #TechInterviews #JavaScript #WebDevelopment #Developers

I just built my first project with Next.js — and I finally understand why so many developers are switching to it. Coming from React, I used to think Next.js was just “React with extra steps”… but actually building with it changed everything. Things that stood out immediately: • Built-in routing (no more manual setup) • Server-side rendering out of the box • Better performance and SEO without extra configuration • Cleaner project structure What surprised me the most wasn’t just the features — it was how much faster I could build something that actually feels production-ready. This project pushed me to think differently about: Data fetching Performance optimization Structuring scalable apps If you're already comfortable with React, learning Next.js is honestly one of the best upgrades you can make right now. Still learning, still improving and open for collaboration — but this is a solid step forward 🚀 live demo : https://lnkd.in/d4C-jHY2 #NextJS #WebDevelopment #Frontend #React #JavaScript #BuildInPublic

🚀 Strengthening my React fundamentals! Here are 10 core concepts every React developer should know (and actually understand 👇) 1️⃣ React is a declarative, component-based library for building UIs 2️⃣ UI updates when state or props change 3️⃣ State = mutable data inside a component 4️⃣ Props = read-only data from parent to child 5️⃣ "useEffect" handles side effects (API calls, timers) 6️⃣ Virtual DOM improves performance 7️⃣ Keys help React track list updates efficiently 8️⃣ Controlled components = form inputs managed by state 9️⃣ Lifting state up helps share data between components 🔟 Custom hooks allow reusable logic 💡 Learning React is not about memorizing—it’s about understanding how UI reacts to data. #ReactJS #FrontendDevelopment #WebDevelopment #LearningInPublic #JavaScript

NodeJS Session - 2 🚀 Introduction to Node.js – From Basics to Execution Getting started with Node.js? Here’s a simple breakdown to build your foundation 👇 🔹 What & Why Node.js
Node.js is a powerful JavaScript runtime built on Chrome’s V8 engine.
It allows you to run JavaScript outside the browser, making it perfect for backend development, APIs, and real-time apps. 💡 Why developers love it:
✔ Fast & scalable (non-blocking I/O)
✔ JavaScript everywhere (frontend + backend)
✔ Huge ecosystem (NPM)
✔ Ideal for real-time applications 🔹 Installation & REPL
Getting started is easy:
1️⃣ Download Node.js (LTS version)
2️⃣ Install & verify using: * node -v * npm -v 🧠 REPL (Read, Eval, Print, Loop):
An interactive environment to quickly test JavaScript code directly in terminal. 🔹 Running JavaScript Outside Browser
Create a simple .js file and run:
👉 node app.js Example: console.log("Hello from Node.js!"); 🔥 Output:
Hello from Node.js! 💬 Mastering Node.js starts with understanding how it runs JavaScript beyond the browser. Once this clicks, backend development becomes much easier. #NodeJS #JavaScript #BackendDevelopment #WebDevelopment #Programming #Coding #Developers #TechLearning

Heard of Node and npm but not sure what they’re for? 🤔 Here’s the simple version: 👉 Node: lets you run JavaScript on your computer 👉 npm: lets you download ready-made code (packages) 🌐 Frontend vs Backend Frontend = what users see (UI in the browser) Backend = what happens behind the scenes (logic, database, automation) When you click an HTML file, JavaScript runs in the frontend (browser) only. 👉 But for backend stuff, you need Node ⚙️ Why do you need them? Because building everything from scratch is slow 😅 With npm, you reuse what others already built With Node, you actually run your app (especially backend) 🍔 Think of it like cooking: 👨🍳 You = the chef 🍽️ Your app = the dish 🛒 npm = where you get ingredients 🔥 Node = where you cook it 💡 Bottom line Without npm → you’d have to make every ingredient yourself Without Node → you have nowhere to run your backend code Together, they make building real apps much faster 🚀 #NodeJS #npm #JavaScript #WebDevelopment #Frontend #Backend #FullStack #LearnsinglecellerLearn #ArRazzak #TheProvider