webcoderspeed.com
40 articles
One synchronous, blocking operation in your Node.js server blocks EVERY concurrent request. JSON.parse on a 10MB payload, a for-loop over 100k items, or a synchronous file read — all of them freeze your event loop and make your entire server unresponsive. Here''s how to find and eliminate blocking I/O.
You deploy a seemingly innocent feature and suddenly CPU spikes from 20% to 95%. Response times triple. The root cause could be a regex gone wrong, a JSON parse on every request, a synchronous loop, or a dependency update. Here''s how to diagnose and fix CPU hotspots in production.
You store a price as a JavaScript float. You retrieve it as 19.99. You display it as 20.000000000000004. Or you store a BigInt user ID as JSON and it becomes the wrong number. Serialization bugs corrupt data silently — no error, just wrong values.
Navigate ESM and CommonJS in Node.js 22. Master require(esm), package.json exports, moduleResolution bundler, and learn when to go full ESM.
Memory leaks in Node.js are insidious — your service starts fine, runs smoothly for hours, then slowly dies as RAM fills up. Every restart buys a few more hours. Here''s how to diagnose, profile, and permanently fix memory leaks in production Node.js applications.
Node.js 22 brings native SQLite, stable test runner, WebSocket client, and TypeScript support. Learn the features that matter for production.
Node.js 18+ includes a native test runner. Learn how node:test replaces Jest and Vitest with zero dependencies, built-in mocking, and sub-second test runs.
Node 22 makes the permission model stable. Restrict file system, network, and child process access with --allow-fs-read, --allow-net, and more. Essential for multi-tenant systems.
Node 22.5+ includes native SQLite via node:sqlite. Run queries without external libraries, dependencies, or server setup. Perfect for CLIs, edge functions, and local-first apps.
Web Streams (WHATWG standard) are now built into Node 18+. Learn when to use ReadableStream vs node:stream, streaming LLM responses, and backpressure handling.
You wrote perfectly async Node.js code — no blocking I/O, no synchronous loops. Yet under load, responses stall and CPU pegs. The culprit is Node.js''s hidden libuv thread pool being exhausted by crypto, file system, and DNS operations. Here''s what''s really happening.
Build scalable monorepos with Turborepo. Master workspace setup, turbo.json pipelines, remote caching, internal packages, dependency graphs, and migration from polyrepos.
Master const type parameters, variadic tuples, decorators, and the new satisfies operator to write type-safe backend code that catches errors at compile time.
Most developers only use git add, commit, push — and they're leaving 80% of Git's power on the table. These advanced Git tips will save you hours every week, make you a better collaborator, and help you out of tricky situations.
React Hooks transformed how we write React components. From useState to useEffect to custom hooks — this guide covers every important hook with practical examples you'll actually use in real projects.
The TypeScript vs JavaScript debate is over — TypeScript won. But understanding why helps you use it better. This guide breaks down every difference, when each makes sense, and how to migrate your JS project to TypeScript painlessly.
Security vulnerabilities can destroy your app, your users, and your reputation overnight. This guide covers the most critical web security threats — XSS, SQL Injection, CSRF, broken auth — and exactly how to prevent them with code examples.
JavaScript array methods are the bread and butter of every developer. map, filter, reduce, find, flat, flatMap — knowing when to use which transforms messy loops into clean, readable code. Here's your complete, practical reference.
Async/await transformed how JavaScript handles asynchronous code. Gone are the days of nested callbacks and messy promise chains. This guide takes you from callbacks to promises to async/await with real-world patterns you'll use every day.
Closures are one of JavaScript's most misunderstood concepts — and one of its most powerful. They're used in React hooks, module patterns, debouncing, memoization, and more. This guide explains closures once and for all, with real examples.
ES2025 brings powerful new features to JavaScript — from better pattern matching to improved async iterators and new Array methods. Here's your complete breakdown of every major feature with practical code examples.
TypeScript is no longer optional — it's the standard for professional JavaScript development in 2026. If you know JavaScript, this guide will get you up to speed with TypeScript in one sitting, with everything explained using practical examples.
Next.js 15 brought major improvements to caching, async APIs, the Turbopack bundler, and React 19 support. This guide covers every significant change with code examples so you know exactly what's new and how to use it.
The Next.js App Router is now the default way to build Next.js apps. It brings file-based routing, layouts, server components, streaming, and more. This guide covers everything you need to master the App Router from scratch.
Next.js Server Actions let you run server-side code directly from your React components — no API routes needed. Form submissions, database mutations, and server logic have never been this clean. Here's everything you need to know.
React Server Components (RSC) are the biggest architectural shift in React's history. They run on the server, fetch data without useEffect, and send zero JavaScript to the client. This guide explains everything about RSC in Next.js with practical patterns.
reixo is a TypeScript-first HTTP client for Node.js, browsers, and edge runtimes. It bundles retries, circuit breaking, request deduplication, OpenTelemetry tracing, typed error returns, offline queuing, caching, and more — zero dependencies. Here's why it's the HTTP client of 2026.
Poor error handling is the
Express remains the most popular Node.js framework for building REST APIs. In this guide, we'll build a complete, production-ready REST API with authentication, validation, error handling, and a database from scratch.
In the world of web development, real-time updates are increasingly becoming a standard requirement for modern web applications. Whether it's updating live scores, notifications, or stock prices, users expect to see changes reflected in real-time without needing to refresh the page.
Discover the power of small tweaks in your JavaScript code that make a big difference! 💻 From optimizing loops to mastering arrow functions, these gems elevate your coding game without breaking a sweat. 💪💎 Ready to unlock the secrets to smoother, more efficient code?
In recent years, React has emerged as one of the most popular JavaScript libraries for building user interfaces, thanks to its component-based architecture and virtual DOM. When combined with TypeScript, a statically-typed superset of JavaScript, React becomes even more powerful, offering enhanced type safety and code maintainability.
In the fast-paced world of web development, JavaScript plays a pivotal role. As developers, we spend a significant amount of time writing and maintaining JavaScript code. In this article, we will delve into the world of JavaScript comments and explore their importance, best practices, and how to effectively use comments within your code.
Data types specify what kind of data can be stored and manipulated within a program. In JavaScript, data types are divided into two parts. Primitive data types and Reference data types. These data types are subdivided into several types.
Variables are a foundational aspect of programming with JavaScript, or any programming language. It’s essential to understand what variable are and what to expect when using them. For the longest time, JavaScript generally had only one way to declare variables, with the var keyword. Since the arrival of ES6 (ES2015), the keywords let and const have been available for variable declaration.
Next.js 13, the latest iteration of the popular React framework, combined with tRPC, an efficient data fetching and API client for React, opens up exciting possibilities for web developers. In this comprehensive guide, we will explore the best practices for using Next.js 13 and tRPC to create high-performance, data-driven web applications.
Node.js, the popular runtime environment known for its versatility and efficiency, has released its latest version, Node.js 17. This release brings a host of enhancements and features that promise to elevate the development experience and boost application performance.
JavaScript, often abbreviated as JS, is a dynamic, versatile, and widely used programming language that plays a pivotal role in web development. This article will provide you with an insightful introduction to JavaScript, covering its history, features, applications, and the reasons why it's an essential language for any aspiring web developer.
Node.js is a powerful, open-source runtime environment for executing JavaScript code outside the web browser. In this article, we'll explore the world of Node.js, its unique features, history, architecture, and real-world applications.
In the ever-evolving world of technology, businesses and developers constantly seek ways to optimize their software systems. Two prominent approaches have emerged in recent years - Middleware and Traditional Functions. These strategies play a crucial role in shaping the digital landscape.