Wasm landing page

src/_data/side-nav.yml

@@ -237,6 +237,8 @@
           permalink: /web/deployment
         - title: Libraries & packages
           permalink: /web/libraries
+        - title: Wasm compilation
+          permalink: /web/wasm
     - title: Environment declarations
       permalink: /guides/environment-declarations
 

src/content/overview.md

@@ -184,8 +184,8 @@ Dart's compiler technology lets you run code in different ways:
   an ahead-of-time (AOT) compiler for producing machine code.
 
 * **Web platform**: For apps targeting the web, Dart can compile for
-  development or production purposes. Its web compiler translates Dart
-  into JavaScript.
+  development or production purposes. Its web compilers translate Dart
+  into JavaScript or WebAssembly.
 
 <img 
   src="/assets/img/Dart-platforms.svg" 
@@ -221,26 +221,31 @@ More information:
 * [Write command-line apps](/tutorials/server/cmdline)
 * [Write HTTP servers](/tutorials/server/httpserver)
 
-#### Dart Web (JavaScript dev & prod) {:#web-platform}
+#### Dart Web (JavaScript dev & prod and WebAssembly) {:#web-platform}
 
 Dart Web enables running Dart code on web platforms powered by
 JavaScript. With Dart Web, you compile Dart code to JavaScript code, which in
 turn runs in a browser—for example, [V8](https://v8.dev/) inside
 [Chrome](https://www.google.com/chrome/).
+Alternatively, Dart code can be compiled to WebAssembly.
 
-Dart web contains two compilation modes:
+Dart web contains three compilation modes:
 
-* An incremental development compiler enabling a fast developer cycle
-* An optimizing production compiler which compiles Dart code to fast,
-  compact, deployable JavaScript. These efficiencies come from
-  techniques such as dead-code elimination.
+* An incremental JavaScript development compiler enabling a fast developer 
+  cycle.
+* An optimizing JavaScript production compiler which compiles Dart code to fast,
+  compact, deployable JavaScript. These efficiencies come from techniques such
+  as dead-code elimination.
+* An optimizing WebAssembly (WasmGC) production compiler which compiles Dart
+  code to super-fast, deployable WebAssembly GC code.
 
 More information:
 
 * [Build a web app with Dart](/web/get-started)
 * [`dart compile js`](/tools/dart-compile#js)
 * [`webdev` tool](/tools/webdev)
 * [Web deployment tips](/web/deployment)
+* [WebAssembly compilation](/web/wasm)
 
 #### The Dart runtime {:#runtime}
 

src/content/tools/dart-compile.md

@@ -117,6 +117,14 @@ The following table shows the subcommands of `dart compile`.
       <br><em><a href="#js">Learn more.</a></em>
     </td>
   </tr>
+  <tr>
+    <td> <code>wasm</code> </td>
+    <td> WebAssembly </td>
+    <td> A portable, binary instruction format for a stack-based virtual machine.
+         Currently under development.
+      <br><em><a href="/web/wasm">Learn more.</a></em>
+    </td>
+  </tr>
 </table>
 
 

src/content/web/wasm.md

@@ -0,0 +1,74 @@
+---
+title: WebAssembly (Wasm) compilation
+description: Learn how to compile your Dart web app to WebAssembly.
+---
+
+The Dart team is excited to add
+[WebAssembly](https://webassembly.org/) as a compilation target when building
+Dart and [Flutter]({{site.flutter}}/wasm) applications for the web.
+
+Development of WebAssembly support remains ongoing,
+which will potentially result in frequent changes. 
+Revisit this page for the latest updates.
+
+:::note
+**Support for Wasm is now in beta!**
+
+WebAssembly support for Dart web is available on the Dart 
+*beta* and *main* [channels](/get-dart#release-channels).
+:::
+
+## WebAssembly support
+
+The current version of Dart compilation to WebAssembly has a number of
+restrictions:
+
+1. It targets WebAssembly with Garbage Collection (aka *WasmGC*), so...
+
+1. The compiled Wasm output currently targets JavaScript environments
+   (such as browsers), and thus currently doesn't support execution in standard
+   Wasm run-times like wasmtime and wasmer. For details, see
+   [issue #53884]({{site.repo.dart.sdk}}/issues/53884)
+
+1. Only Dart's
+   [next-gen JS interop mechanism](/interop/js-interop/)
+   is supported when compiling to Wasm.
+
+## Compiling your web app to Wasm {:#compiling-to-wasm}
+
+We've landed support in the `dart` CLI for invoking the
+`dart2wasm` compiler in the Dart and Flutter `main` channels:
+
+```console
+$ dart help compile wasm
+Compile Dart to a WebAssembly/WasmGC module (EXPERIMENTAL).
+
+Usage: dart compile wasm [arguments] <dart entry point>
+-h, --help                  Print this usage information.
+-o, --output                Write the output to <file name>.
+                            This can be an absolute or relative path.
+-v, --verbose               Print debug output during compilation
+    --enable-asserts        Enable assert statements.
+-D, --define=<key=value>    Define an environment declaration. To specify multiple declarations, use multiple
+                            options or use commas to separate key-value pairs.
+                            For example: dart compile wasm -Da=1,b=2 main.dart
+```
+
+To try Wasm today from the `main` channel:
+
+1. Start with a web app: `dart create -t web mywebapp`
+
+    The template creates a small web app using [`package:web`][],
+    which is necessary to run Wasm.
+    Make sure your web apps are [migrated][] from `dart:html` to `package:web`.
+
+1. Compile with Wasm: `mywebapp$ dart compile wasm web/main.dart`
+
+1. Serve the output: `dart pub global run ` [`dhttpd`]
+
+You can also check out this small example [here](https://github.com/mit-mit/sandbox).
+
+[`package:web`]: {{site.pub-pkg}}/web
+[`dart:js_interop`]: {{site.dart.api}}/{{site.dart.sdk.channel}}/dart-js_interop 
+[migrated]: /interop/js-interop/package-web/
+[`dhttpd`]: {{site.pub-pkg}}/dhttpd