# Ruff WASM
> **⚠️ WARNING: This API is experimental and may change at any time**
An extremely fast Python linter and code formatter, written in Rust.
This is a WASM version of the Ruff API which can be used to lint/format Python in a browser environment.
There are multiple versions for the different wasm-pack targets. See [here](https://rustwasm.github.io/docs/wasm-bindgen/reference/deployment.html) for more info on targets.
- [Bundler](https://www.npmjs.com/package/@astral-sh/ruff-wasm-bundler)
- [Web](https://www.npmjs.com/package/@astral-sh/ruff-wasm-web)
- [Node.js](https://www.npmjs.com/package/@astral-sh/ruff-wasm-nodejs)
## Usage
This example uses the wasm-pack web target and is known to work with Vite.
```ts
import init, { Workspace, type Diagnostic, PositionEncoding } from "@astral-sh/ruff-wasm-web";
const exampleDocument = `print('hello'); print("world")`;
await init(); // Initializes WASM module
// These settings illustrate configuring Ruff
// Settings info: https://docs.astral.sh/ruff/settings
const workspace = new Workspace(
{
"line-length": 88,
"indent-width": 4,
format: {
"indent-style": "space",
"quote-style": "double",
},
lint: {
select: ["E4", "E7", "E9", "F"],
},
},
PositionEncoding.UTF16,
);
// Will contain 1 diagnostic code for E702: Multiple statements on one line
const diagnostics: Diagnostic[] = workspace.check(exampleDocument);
const formatted = workspace.format(exampleDocument);
```
## Versioning
This crate is an internal component of [Ruff](https://crates.io/crates/ruff). The Rust API exposed
here is unstable and will have frequent breaking changes.
This version (0.16.4) is a component of [Ruff 0.16.4](https://crates.io/crates/ruff/0.16.4). The
source can be found [here](https://github.com/astral-sh/ruff/blob/0.16.4/crates/ruff_wasm).
See Ruff's [crate versioning policy](https://docs.astral.sh/ruff/versioning/#crate-versioning) for
details on versioning.