Sometime back I stumbled upon WebAssembly (Wasm), and it had me intrigued. One of those technologies that feel like they’re going to hange the game completely for web development in terms of performance, you know? The more I read on it, the more awesome it became for a frontend developer though! Wasm can allow us to run high-performance code right in our browser almost like native apps would do.

Imagine you’re building a high-performance web application, such as a 3D game, an image editor, or a number-crunching dashboard. You need the app to be fast and fluid, doing all kinds of complicated things without slowing down. But there’s only so far you can go with JavaScript: no matter how much you optimize, there’s scope for code that JavaScript simply can’t run fast.
Web Assembly (Wasm) – With this cool tech now we can run high performance code in-browser almost like you would on native app.

So since I find the talks about WebAssembly very contagious, I decided to compile some explanations so that you could get excited about it as well!

In this post, we’ll learn what WebAssembly is and how it interacts with JavaScript to make your web applications faster and more efficient! Let’s take a look at what WebAssembly has in store for our projects.

What is Web Assembly – In A Nutshell!

Alright, so what actually is WebAssembly or Wasm? It’s basically a supercharged companion to JavaScript. WebAssembly is a low-level binary format that runs in the browser with near-native speed. It’s built for things that are computationally heavy, which JavaScript wouldn’t handle terribly well on its own.

The best part is that WebAssembly isn’t associated with a particular programming language. It’s a language-agnostic platform where code in languages such as C, C++, or Rust can run directly in the browser. Developers can finally start taking high-performance code from other languages and compiling it to WebAssembly to use alongside JavaScript on the web.

Example:

Imagine you’re building a car. JavaScript is the mechanic that does the general work, putting on the wheels and painting the body. WebAssembly is that specialized robot that does all the heavy lifting and detailed welding of the frame. Combined, they make for a speedy and efficient car-building process.

Why WebAssembly is a Game-Changer for Frontend Development

WebAssembly brings several benefits, which are especially handy for frontend developers targeting high performance. Here’s why Wasm is such an important addition to the development community:

Blazing Fast Performance

Wasm code runs nearly as fast as native applications, so you can use it for performance intensive tasks. If you are building an image editor, Wasm can easily deal with real time image processing such as resizing, color adjustment or applying filters and let JavaScript handle the UI.

Consistent Across Browsers

All major browser support WebAssembly i.e Chrome, Firefox, Safari and Edge. That means wherever your user is the Wasm code will run similarly. So, we are guaranteed that our app performance remains consistent and fast.

More Language Choices

With WebAssembly, you’re not limited to JavaScript. You can bring in other languages like C++ or Rust, which are known for their performance and memory efficiency. This is great for projects where speed is critical, or when you want to reuse existing codebases.

Optimized Resource Usage

WebAssembly is developed to be low memory. This makes it apt for the devices with limited resources such as mobile. This is very important as modern applications are expected to perform on all kind of devices.

When Should You Use WebAssembly?

Not every web project needs WebAssembly. For many things, JavaScript is still more than capable: form validation, basic interactivity, DOM manipulation… But if you need it to go faster or you’re working with particularly large amounts of data, here’s when Wasm might save your day:

Graphics-Intensive Apps: Applications which requires 3D rendering i.e. web based gaming or simulation etc.

Real-Time Data Processing: Application which needs fast calculation i.e financial/ scientific analytic tools etc.

Legacy Code on the Web: If you have existing code written in C++ or Rust, WebAssembly allows you to bring it to the web without a complete rewrite.

Example: Running a Physics Simulation in the Browser

Say you’re creating a physics simulation app where users can play with forces, velocities, and gravity. If you do all of these calculations in JavaScript, your browser may not be able to keep up. With WebAssembly, on the other hand, you can perform the heavy computations elsewhere and guarantee smooth animations and real-time response.

Let’s go through a simple example to see how WebAssembly can interface with JavaScript. We are going to write a function in C that calculates the Fibonacci sequence (a performance-heavy task when done with larger numbers) and call it from JavaScript.

Step 1: Write the Function in C
First, create a file named fibonacci.c:

Step 2: Compile the C Code to WebAssembly
To compile C to WebAssembly, you’ll need Emscripten, a tool that converts C/C++ code to Wasm. After installing Emscripten, use this command:

This command will generate two files:

fibonacci.wasm: The WebAssembly binary.
fibonacci.js: A JavaScript file to load the WebAssembly module.

Step 3: Use WebAssembly in JavaScript
Now, create an HTML file to load and run the WebAssembly code:

When you open this file in your browser and click the button, WebAssembly calculates the Fibonacci sequence with high efficiency, without putting strain on JavaScript.

WebAssembly and JavaScript: A Perfect Team

WebAssembly was designed as a complement to, not a replacement of, JavaScript. They work best in tandem: Wasm does the heavy computational lifting and JavaScript handles the user interface logic and browser interactions.

Example Scenario: Data Visualization

Imagine you’re building a data visualization app that needs to work with very large datasets. WebAssembly can handle the data crunching and other performance-sensitive, number-crunching parts of your code while JavaScript can still be used for things like rendering your graphs and charts, providing a nice balance between performance and interactivity.

Real-World Applications of WebAssembly

Figma: The design tool Figma, uses WebAssembly to perform complicated vector graphic operations. This ensures a fast and fluid user interface, as if you were using a native desktop application.

Autodesk AutoCAD: Autodesk uses WebAssembly for its powerful CAD software on the web, enabling engineers to use design tools right in their browser with no installation needed.

Google Earth: Google Earth also utilizes WebAssembly for rendering 3D images and map data to enable users smoothly explore the planet in the browser.

These shows WebAssembly’s capability in delivering desktop grade performance in the browser thereby enabling capabilities which have not been possible in Web applications so far.

Conclusion: Why WebAssembly is the Future of Web Development

WebAssembly is set to revolutionize the web as we know it. By enabling near-native performance in the browser, we can finally build the sort of ambitious applications and experiences that have previously been restricted to native desktop platforms.

For frontend developers, WebAssembly presents an opportunity to start wrangling applications that perform better than anything possible with js alone. Whether you are making a game, doing some data visualization, or just trying to speed up an existing project it behaves nicely with javascript and gives a near native feel of execution.

You can get started by doing some more performance sensitive work in Wasm for your app and see if it is the right feature for you. It might be!