It’s 2025, yet most codebases still misuse Fetch by omitting error checks and implementing broken retries. Here’s how to actually do it right. Introduction You’ve seen this line a thousand times: fetch(“/api/data”).then((res) => res.json()).then(console.log); Looks fine, right?Except it silently fails on 404s, swallows timeouts, and floods logs when the network hiccups. The Fetch API is powerful…

Everything you need to know, from simple GET requests to advanced error handling, retries, and streaming responses. Introduction For years, we used it XMLHttpRequest like it was black magic.Then came fetch(), a modern, promise-based, and far cleaner approach. But here’s the catch: Even experienced developers misunderstand how Fetch actually handles errors, timeouts, and responses. This…

Understand what’s really happening behind Express, Redux, and Koa by building your own middleware system from scratch. Introduction If you’ve ever written something like this in Express: app.use((req, res, next) => { console.log(“Request received!”); next();}); …you’ve already used middleware, but do you know how it actually works? Most developers think middleware is a framework feature. In reality,…

Stop wiring callbacks manually, learn how pub–sub makes your code modular, scalable, and surprisingly elegant. Introduction Let’s be honest, JavaScript apps are full of “when this happens, do that” logic. It’s easy to start with callbacks or addEventListener()but as your app grows, everything ends up tangled together. That’s where the Publish–Subscribe pattern (or Pub–Sub) shines.…

Learn how to limit function calls in high-frequency events like scroll and resize, no Lodash, no magic. Introduction You’ve probably seen this before: window.addEventListener(“scroll”, () => { console.log(“scrolling…”);}); Now open the console and scroll a little. 🔥 Boom, hundreds of logs per second. That’s because the scroll event fires continuously. If you run heavy code (like recalculating…

Both limit how often functions run, but they behave very differently. Let’s finally end the confusion with simple visuals and real examples. Introduction If you’ve ever said “throttle” when you meant “debounce”, you’re not alone. Developers mix them up all the time because both: But they’re not the same thing; in fact, they solve opposite…

Stop your app from firing hundreds of events per second learn how throttling can make your code faster, smoother, and more efficient. Introduction If you’ve ever logged a scroll or resize event in JavaScript, you’ve probably seen this chaos: window.addEventListener(“scroll”, () => console.log(“Scrolling…”)); Now open the console and scroll hundreds of logs per second! 😬…

Forget the theory, here’s how debouncing really behaves in real-world JavaScript apps (with code, visuals, and gotchas). Introduction You’ve probably seen it debounce() mentioned in blog posts or StackOverflow threads. But when someone asks, “How does debounce actually work?”, things get fuzzy. Here’s the truth: Debouncing isn’t magic. It’s just a clever use of setTimeout() and clearTimeout()…

Stop spamming your APIs, optimize your event handlers, and learn how debounce really works from scratch. Introduction If your JavaScript app ever: …you’ve probably needed a debounce function. Most developers just grab it from Lodash (_.debounce) and move on. But do you actually know how debounce works under the hood? In this post, you’ll learn: By the…