Ishwar Chandra Tiwari

Hi 👋 I’m Ishwar. 12+ years in software engineering. I share DSA, system design, and real-world coding insights. Building CodeWithIshwar 🚀

SOLID Principles make code scalable, maintainable, and easier to debug. #codewithishwar #SOLID #CleanCode #SoftwareEngineering #Programming #Java #Backend #SystemDesign #Coding #Developers #TechTwitter #100DaysOfCode #Architecture #FullStackDeveloper

Node.js is single-threaded, but concurrency issues still happen. Race conditions and overlapping async operations are real challenges in scalable systems. That’s why mutexes, transactions, and Redis locks still matter 🚀 #NodeJS #JavaScript #BackendDevelopment #codewithishwar

Git won the popularity war. But Mercurial powered massive engineering workflows at Meta Platforms and Mozilla. 🚀 New newsletter: “Why Mercurial Still Matters in 2026” linkedin.com/pulse/complete… #Mercurial #Git #SoftwareEngineering #CodeWithIshwar

JavaScript is single-threaded. So why do race conditions still exist? 👀 Because async JavaScript is all about execution order. Event Loop → Promises → Microtasks → Race Conditions. That’s the real game. #CodeWithIshwar #javascript #nodejs #reactjs

Most devs don’t struggle with JavaScript. They struggle because they ignore what’s under the hood. JS = • Closures (memory) • Event Loop (async) • Prototypes (inheritance) • Coercion (weird but powerful) #JavaScript #WebDev #Programming #CodeWithIshwar

A simple integer broke my program. Two threads: +1 and -1 Expected: 0 Actual: ❌ random Because value++ is NOT atomic. It’s: Read → Modify → Write Threads can interleave at any step → race condition. #Concurrency #Multithreading #CodeWithIshwar

Redis looks simple — just key-value storage. But underneath, it’s powered by smart data structures: Strings, Hashes, Lists, Sets, Sorted Sets. That’s why Redis isn’t just fast — it’s a data structure engine for real-time systems 🚀 #Redis #DSA #SystemDesign #CodeWithIshwar

There is NO perfect system design. Netflix scaled → changed architecture Amazon trades consistency for availability Uber keeps redesigning systems Reality: 👉 Every system is a trade-off #SystemDesign #Backend #Scalability #codewithishwar

Most developers use indexes. Very few truly understand how they work linkedin.com/pulse/most-dev…

🌐 Type a URL → DNS kicks in 🌐 Cache → Resolver → Root → TLD → IP ⚡ Cache = fast 🐢 No cache = slow #dns #systemdesign #systemdesign #dns #backend #programming #codewithishwar

Scaling too early is a mistake. You don’t scale your system—you scale your problems. #SystemDesign #Scalability #BackendEngineering #SoftwareEngineering #CodeWithIshwar

Production was down. Everything looked normal. That’s when you know: You’re solving a puzzle, not debugging. #programming #systemdesign #codewithishwar

Most devs write code. Few understand what happens after. Your code → AST (Abstract Syntax Tree), not executed as text. Example: a = 2 + 3 * 4 → * before + Code = string AST = logic #CodeWithIshwar #Programming #Developers

🧠 Thread vs Async vs Queue Not alternatives. Different answers. 🧵 Threads → parallel work ⚡ Async → don’t block 📦 Queue → do it later Real systems use all three. Scalability = choosing based on the problem. #SystemDesign #Concurrency #CodeWithIshwar

Check out the latest article in my newsletter: 🧠 Mark & Sweep Isn’t a Language Feature. It’s a System Design Pattern. linkedin.com/pulse/mark-swe… via @LinkedIn

In AI, “nothing” doesn’t exist. Even silence is stored as data. - codewithishwar #AI #MachineLearning #Programming #Developers #Tech

I almost overcomplicated this problem. 😅 LeetCode 3546 — Equal Sum Grid Partition At first: “Try all cuts” ❌ But the trick is simple: If total sum is even → find a prefix = total / 2 That’s it. No brute force. Just clarity. #leetcode #dsa #java #programming #codewithishwar

Most developers solve DP wrong. They only track the best path. But sometimes… your worst path becomes your best. (-ve × -ve = +ve) That’s the trick behind LeetCode 1594. - CodeWithIshwar 🚀 #codewithIshwar

Most devs overcomplicate this problem. They compare every pair → O(n²) Better way 👇 Sort the elements. Minimum absolute difference will always be between adjacent values. Simple. Clean. Efficient. Day 1 of consistency. - CodeWithIshwar 🚀 #leetcode #programming #dsa

Most developers get stuck not because problems are hard. They get stuck because they don’t have a system. Here’s my approach to solve any coding problem: Strong developers don’t guess. - Ishwar Chandra Tiwari | CodeWithIshwar #CodeWithIshwar #leetcode #programming #developers