React & Next.js
React Hooks Masterclass: useState, useEffect, and Custom Hooks Explained
Deep-dive into React Hooks: learn how useState, useEffect, and custom hooks work under the hood with real, runnable code examples and clear mental models.
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All 69 articles
React & Next.js
How React Works Internally: Virtual DOM, Reconciliation, and the Rendering Pipeline
How React's Virtual DOM, reconciliation and diffing work internally, from setState to pixels on screen.
JavaScript
Mastering TypeScript: Interfaces, Generics, and Union Types Explained
TypeScript from the ground up: type annotations, interfaces, type aliases, union and intersection types, generics and tsconfig.
System Design
Realtime Systems Deep Dive: Polling, WebSockets, SSE, and Pub/Sub Explained
Polling, long polling, Server-Sent Events, WebSockets and Pub/Sub compared, with code, trade-offs and guidance on when to use each.
AI & LLMs
How ChatGPT Understands Your Questions: A Deep Dive into LLMs, Tokenization, and Transformers
Deep dive into how ChatGPT works: tokenization, Transformer architecture, self-attention, and sampling — with real Python code examples and diagrams.
System Design
Building Scalable Systems: Caching, Rate Limiting, and Observability
Learn how to build production-grade scalable systems with caching strategies, rate limiting algorithms, and full-stack observability using OpenTelemetry.
React & Next.js
Modern Next.js: The Complete Guide to App Router, Server Components, and Full-Stack Architecture
Master modern Next.js architecture: App Router, layouts, Server Components, API Routes, and Server Actions with real production patterns and code examples.
React & Next.js
React Fundamentals: Components, JSX, State, and Re-rendering Explained
Learn React from the ground up: why it exists, how JSX compiles, how components and props work, and how state drives automatic UI re-rendering.
React & Next.js
Next.js Explained: Why It Became the Default React Framework
Learn why Next.js was created, how it solves React's core limitations with SSR, SSG, Server Components, and file-based routing, and when to use it.
AI & LLMs
Where RAG Fails: A Deep Dive Into the Real Limitations of Retrieval-Augmented Generation
RAG improves LLM answers but does not guarantee correctness. The real failure modes: poor retrieval, bad chunking, hallucination and stale data.
Node.js & Express
Securing Web Apps: Password Hashing, RBAC, OAuth 2.0, and OpenID Connect Explained
Secure web apps with bcrypt password hashing, role-based access control, OAuth 2.0 and OpenID Connect, with code and diagrams.
Node.js & Express
Modern Database Access in JavaScript: Prisma, Drizzle, and ORMs Explained
Prisma vs Drizzle for TypeScript: SQL vs NoSQL, data modeling, migrations, and how to choose the right database tool for your project.
React & Next.js
Expo Router vs React Navigation in 2026: A Practical Guide for React Native Developers
Expo Router vs React Navigation in 2026: when to use each, with real code for auth flows, nested layouts and production app structure.
React & Next.js
How Instagram, WhatsApp, Uber & Netflix Would Be Built Today Using Expo Router
How to structure a large React Native app with Expo Router: feature modules, route groups and shared layouts, using apps like Instagram and Uber as examples.
Node.js & Express
Blocking vs Non-Blocking Code in Node.js: Why It Makes or Breaks Your Server
Learn how blocking code kills Node.js server performance and how non-blocking async I/O fixes it. Real file and DB examples with benchmarks.
JavaScript
JavaScript Map and Set: The Data Structures You Should Be Using Instead of Objects and Arrays
Learn when to use JavaScript Map and Set instead of Object and Array. Includes performance benchmarks, real code examples, and clear trade-offs.
JavaScript
JavaScript Destructuring: Write Less Code, Extract More Value
Learn JavaScript destructuring with real before/after examples. Covers array destructuring, object destructuring, default values, and function parameters.
Node.js & Express
REST API Design with Express.js: A Practical Guide to Resources, Routes, and HTTP Methods
Learn REST API design with Express.js. Build a users API with GET, POST, PUT, DELETE routes, correct status codes, and clean route conventions.
JavaScript
Understanding the `this` Keyword in JavaScript: What It Is and How Calling Context Controls It
Learn how the `this` keyword works in JavaScript — global scope, object methods, callbacks, and arrow functions — with clear runnable examples.
Node.js & Express
Express Middleware Explained: How the Request Pipeline Actually Works
Learn what Express middleware is, how next() controls the request pipeline, and see real examples for logging, auth, and validation.
Node.js & Express
Handling File Uploads in Express with Multer: A Complete Developer Guide
Learn how to handle single and multiple file uploads in Express using Multer. Covers storage config, validation, error handling, and serving files.
Node.js & Express
What is Node.js? JavaScript on the Server Explained
Learn what Node.js is, how V8 and libuv power it, and why its event-driven model makes it ideal for I/O-heavy server-side applications.
Node.js & Express
JWT Authentication in Node.js: A Complete Developer Guide
Learn how JWT works and implement stateless authentication in Node.js with Express — login flow, route protection, and complete working code.
Node.js & Express
Creating Routes and Handling Requests with Express.js: A Practical Guide
Learn how to create routes and handle GET/POST requests in Express.js. Includes raw Node.js comparison, complete working code, and routing best practices.
Node.js & Express
Setting Up Your First Node.js Application: A Step-by-Step Guide from Install to HTTP Server
Install Node.js, use the REPL, run your first script, and build a working HTTP server from scratch — no frameworks, no dependencies.
Node.js & Express
How Node.js Handles Thousands of Requests on a Single Thread: A Deep Dive into the Event Loop
Learn how Node.js uses the event loop and libuv to handle thousands of concurrent requests on a single thread — with real code examples.
Node.js & Express
URL Parameters vs Query Strings in Express.js: When to Use Each and Why
Learn the difference between URL parameters and query strings in Express.js, when to use each, and how to access them with real working code examples.
Node.js & Express
Sessions vs JWT vs Cookies: A Practical Guide to Choosing the Right Authentication Approach
Understand the real differences between sessions, JWTs, and cookies. Learn when to use each auth approach with working Node.js
Node.js & Express
Async Code in Node.js: Callbacks and Promises Explained with Real Examples
Learn why async code exists in Node.js, how callbacks work, why they fail at scale, and how Promises solve it with real, runnable examples.
JavaScript
Synchronous vs Asynchronous JavaScript: How the Language Actually Executes Code
How JavaScript runs one thing at a time, and how asynchronous code hands off slow work like API calls and timers without freezing the page.
JavaScript
Async/Await in JavaScript: Writing Cleaner Asynchronous Code
Async/await is syntax over Promises that makes async code read top to bottom. How it works, error handling with try/catch, and parallel calls with Promise.all.
Git & Dev Tools
The Linux File System Hunting Expedition
What the Linux filesystem reveals about a running system: /etc, /proc, /var/log and more, explored hands-on from the command line.
JavaScript
Array Flatten in JavaScript: Every Approach Explained
From nested chaos to clean lists — understand, implement, and ace every flatten question.
JavaScript
Spread vs Rest Operators in JavaScript: Expanding vs Collecting
A flow diagram showing a source array [1, 2, 3] being unpacked by the ... spread syntax into three individual amber-coloured elements, which then merg
Node.js & Express
Setting up Express.js with TypeScript
TypeScript catches Express bugs at compile time, not in production. This guide sets up strict typing, hot-reload dev workflow, and a compiled producti
JavaScript
Error Handling in JavaScript: Try, Catch, Finally
Learn how structured error handling in JavaScript turns crashes into recoverable moments with real code, clear patterns, and zero fluff.
JavaScript
The new Keyword in JavaScript: What Actually Happens
What JavaScript does step by step when you call a function with new: object creation, prototype linking, binding this, and what goes wrong without new.
JavaScript
Template Literals in JavaScript: Write Strings Like a Human
Template literals in JavaScript: embedded expressions, multi-line strings and tagged templates, and how they replace string concatenation.
JavaScript
String Polyfills and Common Interview Methods in JavaScript
Implement String methods like includes, trim and repeat from scratch: how string polyfills work and the string questions that come up in interviews.
JavaScript
Callbacks in JavaScript: Why They Exist
Why callbacks exist in JavaScript, how they work with async code like timers and file reads, and where nesting them starts to hurt.
JavaScript
JavaScript Modules: Import and Export Explained
How JavaScript modules work: named and default exports, imports, and how splitting code into modules keeps a project maintainable.
Node.js & Express
Why Does setImmediate Sometimes Run Before setTimeout(fn, 0)?
Why setImmediate sometimes runs before setTimeout(fn, 0) in Node.js and sometimes after: the event loop phases and timer precision behind it.
JavaScript
The Magic of this, call(), apply(), and bind() in JavaScript
How this works in JavaScript functions and objects, and how call(), apply() and bind() let you control it, with a side-by-side comparison and exercises.
JavaScript
Function Declaration vs Function Expression: What's the Difference?
Function declarations vs function expressions in JavaScript: syntax, hoisting, when to use each, and a quick look at arrow functions.
JavaScript
JavaScript Operators: The Basics You Need to Know
JavaScript operators explained: arithmetic, comparison, logical and assignment operators, with == vs === and a short practice exercise.
JavaScript
Understanding Objects in JavaScript — A Developer's Exploration
JavaScript objects from the ground up: key-value pairs, creating objects, reading, updating and deleting properties, and looping through keys.
JavaScript
Control Flow in JavaScript: If, Else, and Switch Explained
How JavaScript decides which code runs: if, else if, else and switch statements, with examples and when to use each.
JavaScript
Understanding Variables and Data Types in JavaScript
Real-life box analogy to introduce variables intuitively All 3 declaration types (var, let, const) with clear examples and when to use each Comparison
JavaScript
Arrow Functions in JavaScript: A Simpler Way to Write Functions
An arrow function is just a shorter, more modern way to write a function in JavaScript. That's honestly all it is. It was introduced in ES6 (2015) and
JavaScript
The Chai Stall Promise System: How Hitesh Bhaiya Manages Orders
JavaScript Promises aren't complicated once you stop thinking of them abstractly.
JavaScript
Top 10 JavaScript Array Methods You Probably Haven't Used Yet
Ten JavaScript array methods beyond the basics, including copyWithin, reduceRight, with and flatMap, plus a Shinchan-story warm-up on push, pop, slice, map and find.
System Design
How I Broke Down WhatsApp's System Design — And What I Learned Along the Way
Understand WhatsApp system design: requirements, architecture, databases, scaling, encryption, protocols, and failure handling insights
Networking & Web Basics
Understanding HTML Tags and Elements: The Building Blocks of the Web
Learn the essentials of HTML tags and elements, their structure, and how to use them to create webpages. Perfect for beginners
Git & Dev Tools
Emmet for HTML: A Beginner's Guide to Writing Faster Markup
Learn to write HTML faster and more efficiently with Emmet. Discover shortcuts, features, and tips for boosting your coding workflow
Networking & Web Basics
CSS Selectors 101: Targeting Elements with Precision
Learn the art of CSS selectors to precisely style your web elements, improve efficiency, and enhance your web development skills
Networking & Web Basics
How a Browser Works: A Beginner-Friendly Guide to Browser Internals
Discover what happens behind the scenes when you load a webpage, from typing a URL to rendering pixels on your screen
Networking & Web Basics
TCP vs UDP: When to Use What, and How TCP Relates to HTTP
Discover the key differences between TCP and UDP and learn how they relate to HTTP in this informative guide
Networking & Web Basics
TCP Working: 3-Way Handshake & Reliable Communication
Discover how TCP ensures reliable internet communication with its 3-way handshake process and safeguards against data loss and corruption
Networking & Web Basics
Getting Started with cURL: A Simple Guide for Beginners
Beginner's guide to cURL: Learn how to send server requests directly from your terminal without a browser. Perfect for API testing and automation!
Networking & Web Basics
Understanding Network Devices: The Complete Guide for Beginners
Beginner's guide to essential network devices supporting internet infrastructure; ideal for tech or web development newcomers
Career
From Tier-3 College to IBM: My Real Journey and Honest Tips
Journey from a tier-3 college to IBM: My story, struggles, rejections, and tips to breaking into tech giants
Networking & Web Basics
How DNS Resolution Works: A Simple Guide for Beginners
Learn how DNS resolution converts domain names to IP addresses, step by step, with explanations of root, TLD, and authoritative name servers
Networking & Web Basics
DNS Record Types Explained: The Complete Beginner's Guide
Learn about DNS record types and how they direct web traffic, emails, and domain control through simple examples and explanations
Git & Dev Tools
Why Version Control Exists: The Pendrive Problem
Discover the chaos of software development prior to version control systems and how they revolutionized teamwork and project management
Git & Dev Tools
Git for Beginners: Basics and Essential Commands
Learn Git basics and essential commands for tracking code changes, collaborating, and maintaining project history with this beginner-friendly guide
Git & Dev Tools
Git Internals: Why Your Monorepo Strategy Depends on Understanding Object Storage
How Git stores blobs, trees and commits, and why that object model should shape your monorepo vs multi-repo decision.
AI & LLMs
Mastering RAG (Retrieval-Augmented Generation): A Step-by-Step Guide for Developers
Learn RAG (Retrieval-Augmented Generation) step by step—chunking, embeddings, vector databases, query retrieval, and LLM integration.
AI & LLMs
Agents vs LLM: Why Brains Alone Aren’t Enough
The difference between an LLM and an AI agent: how agents add tools, memory and actions to a language model, with a small agent that fetches news and movies.
AI & LLMs
Mastering Prompting Techniques: From Zero-Shot to Persona-Based
Learn prompting techniques like zero-shot, one-shot, chain of thought, self-consistency, and persona-based with easy examples.