Azizul Rabby Chowdhury’s Post

𝗤𝘂𝗶𝗰𝗸 𝘁𝗶𝗽: 𝗡𝗲𝘃𝗲𝗿 𝗿𝗲𝘁𝘂𝗿𝗻 𝗻𝘂𝗹𝗹. 𝗥𝗲𝘁𝘂𝗿𝗻 𝗲𝗺𝗽𝘁𝘆 𝗮𝗿𝗿𝗮𝘆𝘀. ✅ Stop returning null when a list has no results. Return an empty array instead. 𝗕𝗮𝗱: function getUsers() {  return users.length > 0 ? users : null; } 𝗚𝗼𝗼𝗱: function getUsers() {  return users || []; } 𝗪𝗵𝘆 𝗶𝘁 𝗺𝗮𝘁𝘁𝗲𝗿𝘀: ❌ Null forces every caller to check before iterating   ❌ Leads to "Cannot read property of null" crashes   ❌ Creates defensive code everywhere   ❌ Makes chaining operations impossible ✅ Empty arrays can be iterated safely (zero loops, no crash)   ✅ Works with map, filter, reduce without checks   ✅ Cleaner code throughout your application Same applies to objects: return {} instead of null when appropriate. Let your data structures be forgiving. Your team will thank you. 🙏 . . . #JavaScript #BestPractices #CleanCode #WebDevelopment #Programming

Most people think the Event Loop just "manages async code." It actually plays favourites. I assumed every callback waited in the same line. Turns out, there are two queues — and they don't get equal treatment. The moment the call stack goes empty, the Event Loop doesn't just grab the next available function. It checks the Microtask Queue first — always. 𝐏𝐫𝐨𝐦𝐢𝐬𝐞𝐬 𝐚𝐧𝐝 𝐟𝐞𝐭𝐜𝐡() 𝐜𝐚𝐥𝐥𝐛𝐚𝐜𝐤𝐬 𝐥𝐢𝐯𝐞 𝐡𝐞𝐫𝐞. 𝐓𝐡𝐞𝐲 𝐜𝐮𝐭 𝐭𝐡𝐞 𝐥𝐢𝐧𝐞, 𝐞𝐯𝐞𝐫𝐲 𝐬𝐢𝐧𝐠𝐥𝐞 𝐭𝐢𝐦𝐞. Regular callbacks — button clicks, setTimeout — wait in the Callback Queue. They only get their turn once the Microtask Queue is fully drained. So the hierarchy is clear: → Call Stack executes → Microtask Queue gets priority when stack empties → Callback Queue runs only after microtasks are done One event loop. Two queues. One clear winner. Next time your async code behaves unexpectedly — check which queue it's sitting in. 🔍 → Agree or disagree? Tell me below. #BuildingInPublic #JavaScript #SoftwareEngineering #DeveloperJourney #LearningInPublic #Programming #TechCommunity #WebDevelopment

I spent HOURS debugging… and the bug was just ONE line. 😅 Everything looked fine. No syntax errors. No warnings. But the output? Completely wrong. console.log([] == false); // true console.log([] === false); // false Wait… what? 🤯 How can the same values give different results? Then it hit me — one of JavaScript’s most confusing concepts: 👉 Type Coercion Here’s what’s happening behind the scenes: "[] == false" ➡ JavaScript converts both values ➡ becomes "0 == 0" ➡ ✅ true "[] === false" ➡ Strict comparison (no conversion) ➡ ❌ false Same values. Different rules. Completely different results. ⚠️ This is where many bugs are born — not because we don’t know JavaScript… but because JavaScript behaves unexpectedly. 💡 Lesson (relearned the hard way): Always prefer "===" over "==" ✔ "===" → checks value + type ❌ "==" → tries to be “smart” (and gets risky) Sometimes debugging isn’t about writing more code… it’s about understanding how the language actually works. Have you ever faced a bug that made you question everything? 👇 #JavaScript #Debugging #WebDevelopment #Programming #Developers #Coding #SoftwareEngineering #LearnToCode #TechLife

Stop scrolling. This one tiny mistake silently breaks your code. No error. No warning. Still WRONG. 👇 if (age = 18) Looks normal, right? It’s not. One symbol. Huge damage. This bug can: • Break your logic silently • Waste hours of debugging • Make you doubt your skills And the worst part? Almost every beginner makes it. But here’s what it taught me: Programming isn’t about writing more code. It’s about understanding what your code is actually doing. Because the most dangerous bugs don’t crash your program. They look correct. But they aren’t. So next time your code feels off: Slow down. Check the basics. Question the logic. That’s how real developers grow. 👇 Your turn: What’s one bug that taught you a lesson you won’t forget? #learncoding #debugging #webdevelopment #javascript #100daysofcode #developerslife

Hot take: Console.log is actually a perfectly fine debugging tool. (hear me out) I spent 20 minutes debugging a React bug last week. A senior dev fixed the same bug in 2 minutes. Same experience. Same skills. Same code. None of that is why I'm posting this. Here's what actually happened: I was guessing. Adding logs. Refreshing. Checking console. Adding more logs. Repeating this cycle like a broken record. He wasn't guessing. He set one breakpoint. Stepped through 3 lines. Saw the exact problem. Done. The difference wasn't intelligence. It was tooling. I've been coding for years and never properly learned the debugger. Not because I'm lazy. Because console.log "worked." But "works eventually" isn't the same as "works efficiently." That's not on any bootcamp curriculum. No tutorial mentions this. Everyone just uses console.log because everyone else does. What I actually got from learning the debugger wasn't speed. It was understanding. I stopped guessing why my code breaks. I started seeing exactly how it executes. I stopped being reactive. I started being intentional. If you're still spamming console.log to fix bugs, you're not bad at debugging. You just don't know there's a better tool. Try setting ONE breakpoint this week instead of adding console.log. Just once. See what happens. Your future self (the one who debugs in minutes, not hours) will thank you. Full breakdown: https://lnkd.in/g2bbeRkg 🔥 #WebDevelopment #JavaScript #Debugging #DeveloperTools #CodingTips #Programming #SoftwareEngineering #LearnToCode #WebDev #TechCareer #JuniorDeveloper #CodeNewbie #100DaysOfCode #DevCommunity #ReactJS #3Qverse

I once spent 6 hours debugging a production issue. The logs looked fine. The tests passed. The code made sense. Turns out? I was console.logging a stale variable before the async call had even resolved. Six. Hours. That day taught me more than any tutorial ever could: → Async bugs don't always throw errors. They just silently lie to you. → "It works on my machine" is a symptom, not an answer. → The first place you look is almost never the problem. The best debugging skill isn't knowing your tools. It's knowing how to question your own assumptions. What's the hardest bug you've ever had to track down? Drop it below 👇 #softwareengineering #javascript #debugging #webdev #coding

Sharing beginner-friendly notes on Advanced Functions in JavaScript 🧠 Covered two of the most important concepts every JS developer needs to master, Closures and Higher-Order Functions. The guide walks through how closures "remember" their lexical scope, enabling data privacy, memoization, and function factories. Also explored essential Higher-Order Functions like map, filter, reduce, and practical utilities like debounce, throttle, curry, and compose with clear examples and visual diagrams. A practical guide for understanding how functions truly work under the hood. Feedback and suggestions are welcome! #JavaScript #Coding #Learning #Programming

Small JavaScript bugs keep escaping to production and breaking critical user flows. Debugging inconsistent runtime behavior steals time from feature delivery. ────────────────────────────── Array.reduce() for Accumulation Let’s dive into how Array.reduce() can simplify your data accumulation tasks. Have you used it before? #javascript #programming #webdevelopment #codingtips ────────────────────────────── Core Concept Array.reduce() is a powerful method for transforming an array into a single value. Have you ever struggled with accumulating values from an array? This method can make that task easier! Key Rules • The first parameter is a callback function that processes each element. • The second parameter is the initial value for the accumulator. • Always return the updated accumulator at the end of your callback function. 💡 Try This const numbers = [1, 2, 3, 4]; const sum = numbers.reduce((acc, num) => acc + num, 0); console.log(sum); // 10 ❓ Quick Quiz Q: What does the reduce method return? A: It returns a single accumulated value from the array. 🔑 Key Takeaway Use Array.reduce() to streamline your data accumulation and simplify your code!

One Command to Build a NestJS Resource! 🚀 Did you know you can create a full feature in NestJS with just one command? Type this in your terminal: $ nest g resource product It automatically creates everything for you: ✅ Controller: To handle requests. ✅ Service: To handle logic. ✅ Module: To organize the code. ✅ Entity: For the database structure. ✅ DTOs: For data validation. No more creating files one by one. It’s fast, clean, and saves so much time! Have you tried this command yet?🤔 Let me know in the comments! 👇 #NestJS #Coding #WebDev #Backend #Programming