wasm-bindgen

    Facilitating high-level interactions between Wasm modules and JavaScript.

    Guide (main branch) (https://wasm-bindgen.github.io/wasm-bindgen/)
     | 
    API Docs (https://docs.rs/wasm-bindgen)
     | 
    Contributing (https://github.com/wasm-bindgen/wasm-bindgen/blob/master/CONTRIBUTING.md)
     | 
    Chat (https://discord.gg/xMZ7CCY)

  Built with 🦀🕸 by The Rust and WebAssembly Working Group (https://rustwasm.github.io/)

## Install `wasm-bindgen-cli`

You can install it using `cargo install`:

```
cargo install wasm-bindgen-cli
```

Or, you can download it from the
[release page](https://github.com/wasm-bindgen/wasm-bindgen/releases).

If you have [`cargo-binstall`](https://crates.io/crates/cargo-binstall) installed,
then you can install the pre-built artifacts by running:

```
cargo binstall wasm-bindgen-cli
```

## Example

Import JavaScript things into Rust and export Rust things to JavaScript.

```rust
use wasm_bindgen::prelude::*;

// Import the `window.alert` function from the Web.
#[wasm_bindgen]
extern "C" {
    fn alert(s: &str);
}

// Export a `greet` function from Rust to JavaScript, that alerts a
// hello message.
#[wasm_bindgen]
pub fn greet(name: &str) {
    alert(&format!("Hello, {}!", name));
}
```

Use exported Rust things from JavaScript with ECMAScript modules!

```js
import { greet } from "./hello_world";

greet("World!");
```

## Features

* **Lightweight.** Only pay for what you use. `wasm-bindgen` only generates
  bindings and glue for the JavaScript imports you actually use and Rust
  functionality that you export. For example, importing and using the
  `document.querySelector` method doesn't cause `Node.prototype.appendChild` or
  `window.alert` to be included in the bindings as well.

* **ECMAScript modules.** Just import WebAssembly modules the same way you would
  import JavaScript modules. Future compatible with [WebAssembly modules and
  ECMAScript modules integration][wasm-es-modules].

* **Designed with the ["Web IDL bindings" proposal][webidl-bindings] in mind.**
  Eventually, there won't be any JavaScript shims between Rust-generated wasm
  functions and native DOM methods. Because the Wasm functions are statically
  type checked, some of those native methods' dynamic type checks should become
  unnecessary, promising to unlock even-faster-than-JavaScript DOM access.

[wasm-es-modules]: https://github.com/WebAssembly/esm-integration
[webidl-bindings]: https://github.com/WebAssembly/proposals/issues/8

## Guide

[**📚 Read the `wasm-bindgen` guide here! 📚**](https://wasm-bindgen.github.io/wasm-bindgen/)

## API Docs

- [wasm-bindgen](https://docs.rs/wasm-bindgen)
- [js-sys](https://docs.rs/js-sys)
- [web-sys](https://docs.rs/web-sys)
- [wasm-bindgen-futures](https://docs.rs/wasm-bindgen-futures)

## MSRV Policy

* Libraries that are released on [crates.io](https://crates.io) have a MSRV of v1.71.
* CLI tools and their corresponding support libraries have a MSRV of v1.82.

The project aims to maintain a 2-year MSRV policy for libraries (meaning we support Rust versions released within the last 2 years), but with a shorter MSRV policy for the CLI. Changes to the MSRV may be made in patch versions, and will be logged in the CHANGELOG and MSRV history below.

### MSRV History

| Version | Library MSRV | CLI MSRV | Date       |
|---------|--------------|----------|------------|
| 0.2.106 | 1.71         | 1.82     | 2025-11-xx |
| 0.2.103 | 1.57         | 1.82     | 2025-09-17 |
| 0.2.93  | 1.57         | 1.76     | 2024-08-13 |

## License

This project is licensed under either of

 * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
   http://www.apache.org/licenses/LICENSE-2.0)
 * MIT license ([LICENSE-MIT](LICENSE-MIT) or
   http://opensource.org/licenses/MIT)

at your option.

## Contribution

**[See the "Contributing" section of the guide for information on hacking on `wasm-bindgen`!][contributing]**

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this project by you, as defined in the Apache-2.0 license,
shall be dual licensed as above, without any additional terms or conditions.

[contributing]: https://wasm-bindgen.github.io/wasm-bindgen/contributing/index.html
