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If you’ve ever written JavaScript, you’ve never had to write code that says “delete this object, I’m done with it.” That’s because there’s a process called garbage collection running in the background to save you the hassle. Most of the time this process works smoothly and invisibly. But it can also cause an app to suddenly start stuttering for no obvious reason if you don’t manage it effectively. This post will give you the tools to do just that.

console.log() in TypeScript allows us to print values to the browser console or terminal, so we can inspect our code while it runs. However, the workflow can take some getting used to: in most projects, TypeScript is compiled into JavaScript, which is then executed by a JavaScript runtime. Whether you’re debugging a React component, a Node.js script or a backend application, it’ll get easier once you’re familiar with these nuances.

Memory leaks are the bugs that really creep up on you. One minute your app is running perfectly, then suddenly it slows to a crawl or crashes. We don’t get a warning with memory leaks, so we need to prepare proactively and be ready when they hit. This means we need to: This guide is here for all of that.

An effective JavaScript debugging process is vital for any web developer. Over 95% of the web is built with JavaScript code, but the language carries its own distinct challenges due to its unique runtime model. This guide will help you master these challenges and become truly fluent in the Internet’s first language. You’ll learn about: You’ll leave with a process that works in any case, no matter how edgy.

A JavaScript array allows us to group related data like product names, user IDs, log entries, cart items, or API results. Arrays play a vital role in all kinds of user functions, from shopping carts to game scores. However the sheer flexibility of JavaScript arrays can also cause mistakes around mutation, copying, sorting, and searching. Soo we’ve put together this post to show you.

If you’ve worked with Node.js in production, you already know that streams are not a niche feature. They are part of the foundation. They power how data moves through systems, how I/O is handled, and ultimately, how applications scale. For years, that foundation has held up remarkably well. At the same time, many developers—junior and senior alike—have shared a similar feeling: while streams are powerful, they don’t always feel natural to work with.

Imagine you’re mechanic trying to fix a car. There’s this magic piece of kit that allows you to pause the engine and see inside every moving part. You can tweak parts live, test changes instantly and measure which parts are slowing the whole thing down. This is JavaScript debugging in Chrome. Using Chrome DevTools, you can pause execution, inspect variables and scope, and follow code as it runs. So you can see what the code is actually doing at runtime, without assumptions.

And more to the point… why do I need to read a whole blog post on it? Two good questions. Well when we’re debugging, stepping removes the guesswork by letting us watch the logic unfold step-by-step. We can pause the code, go through the execution one instruction at a time and isolate the exact point where the bad stuff happens. This is one of the most reliable ways to understand why a bug happens, not just where it shows up. It also shines a microscope on our code flow, showing us.

The JavaScript debugger statement is a built-in keyword that tells the JavaScript engine to pause execution at a specific line of code. When execution stops, you can inspect variables, function scope, and the call stack using developer tools. It is commonly used during development to analyze how values change and where logic breaks, without relying on repeated logging or assumptions. No more guesswork. No more partial truths.

There’s something powerful about stepping away from your day-to-day work and being surrounded by people asking the same questions you’ve been thinking about: At JSConf Spain, those answers don’t come from a single talk. They emerge from patterns — ideas that repeat across different speakers, different companies, and different perspectives.