WebAssembly é um novo tipo de código que pode ser executado nos navegadores da Web modernos — é uma linguagem de montagem de baixo nível com um formato binário compacto que é executado com desempenho quase nativo e fornece linguagens como C/C++ com um destino de compilação para que possam ser executadas na Web. Este também é projetado para funcionar com JavaScript, permitindo que ambos trabalhem juntos.

In a Nutshell

WebAssembly has huge implications for the web platform — it provides a way to run code written in multiple languages on the web at near native speed, with client apps running on the web that previously couldn’t have done so.

WebAssembly is designed to complement and run alongside JavaScript — using the WebAssembly JavaScript APIs, you can load WebAssembly modules into a JavaScript app and share functionality between the two. This allows you to take advantage of WebAssembly's performance and power and JavaScript's expressiveness and flexibility in the same apps, even if you don't know how to write WebAssembly code.

And what's even better is that it is being developed as a web standard via the W3C WebAssembly Working Group and Community Group with active participation from all major browser vendors.


WebAssembly concepts
Get started by reading the high-level concepts behind WebAssembly — what it is, why it is so useful, how it fits into the web platform (and beyond), and how to use it.
Compiling a New C/C++ Module to WebAssembly
When you’ve written code in C/C++, you can then compile it into .wasm using a tool like Emscripten. Let’s look at how it works.
Compiling an Existing C Module to WebAssembly
A core use-case for WebAssembly is to take the existing ecosystem of C libraries and allow developers to use them on the web.
Loading and running WebAssembly code
After you have a .wasm, this article covers how to fetch, compile and instantiate it, combining the WebAssembly JavaScript API with the Fetch or XHR APIs.
Using the WebAssembly JavaScript API
Once you've loaded a .wasm module, you'll want to use it. In this article we show you how to use WebAssembly via the WebAssembly JavaScript API.
Exported WebAssembly functions
Exported WebAssembly functions are the JavaScript reflections of WebAssembly functions which allow calling WebAssembly code from JavaScript. This article describes what they are.
Understanding WebAssembly text format
This article explains the wasm text format. This is the low-level textual representation of a .wasm module shown in browser developer tools when debugging.
Converting WebAssembly text format to wasm
This article provides a guide on how to convert a WebAssembly module written in the text format into a .wasm binary.

Referência de API

WebAssembly (en-US)
This object acts as the namespace for all WebAssembly related functionality.
WebAssembly.Module() (en-US)
A WebAssembly.Module object contains stateless WebAssembly code that has already been compiled by the browser and can be efficiently shared with Workers, and instantiated multiple times.
WebAssembly.Instance() (en-US)
A WebAssembly.Instance object is a stateful, executable instance of a ModuleInstance objects contain all the Exported WebAssembly functions that allow calling into WebAssembly code from JavaScript.
WebAssembly.instantiateStreaming() (en-US)
The WebAssembly.instantiateStreaming() function is the primary API for compiling and instantiating WebAssembly code, returning both a Module and its first Instance.
WebAssembly.Memory() (en-US)
A WebAssembly.Memory object is a resizable ArrayBuffer that holds the raw bytes of memory accessed by an Instance.
WebAssembly.Table() (en-US)
A WebAssembly.Table object is a resizable typed array of opaque values, like function references, that are accessed by an Instance.
WebAssembly.CompileError() (en-US)
Creates a new WebAssembly CompileError object.
WebAssembly.LinkError() (en-US)
Creates a new WebAssembly LinkError object.
WebAssembly.RuntimeError() (en-US)
Creates a new WebAssembly RuntimeError object.



Especificação Estado Comentário
WebAssembly JavaScript Interface Working Draft Initial draft definition of the JavaScript API.

Compatibilidade de navegador

BCD tables only load in the browser

Consultar também