---
title: "Claude Code WebAssembly Rust"
description: "Configures Claude Code for high-performance WebAssembly development with Rust and seamless browser integration."
category: "configuration"
tags: ["claude-code", "webassembly", "rust", "wasm", "performance", "browser"]
tech_stack: ["rust", "webassembly", "wasm-pack", "js-sys", "web-sys", "wasm-bindgen"]
---

This configuration helps you create a solid environment for developing high-performance WebAssembly applications using Rust.

### Configuration Overview
With this setup, you can efficiently build WebAssembly applications in Rust. You'll use tools like `wasm-pack` to build, package, and publish to npm, along with `wasm-bindgen` for smooth compatibility with JavaScript.

### Prerequisites
Before you start, make sure you have the following installed:

- **Rust**: Get the latest stable version from [rust-lang.org](https://www.rust-lang.org/).
- **wasm-pack**: Install it using Cargo by running:
  ```bash
  cargo install wasm-pack
  ```
- **Node.js**: Make sure you have Node.js version 12 or later.
- **npm**: This comes bundled with Node.js. You can check if it's installed by typing:
  ```bash
  npm -v
  ```

### Installation & Setup
Let’s walk through the setup process:

1. **Create a new Rust project**:
   ```bash
   cargo new --lib my_wasm_project
   cd my_wasm_project
   ```
2. **Add dependencies** to your `Cargo.toml` file:
   ```toml
   [lib]
   crate-type = ["cdylib"]

   [dependencies]
   wasm-bindgen = "0.2"
   ```
3. **Write your Rust code** in `src/lib.rs`:
   ```rust
   use wasm_bindgen::prelude::*;

   #[wasm_bindgen]
   pub fn greet(name: &str) -> String {
       format!("Hello, {}!", name)
   }
   ```
4. **Build your project** with wasm-pack:
   ```bash
   wasm-pack build --target web
   ```
5. **Create a simple HTML file** for testing in the `my_wasm_project` directory:
   ```html
   <!DOCTYPE html>
   <html lang="en">
   <head>
       <meta charset="UTF-8">
       <meta name="viewport" content="width=device-width, initial-scale=1.0">
       <title>My WASM Project</title>
       <script type="module">
           import init, { greet } from './pkg/my_wasm_project.js';
           async function run() {
               await init();
               console.log(greet("World"));
           }
           run();
       </script>
   </head>
   <body>
       <h1>Check the console for output!</h1>
   </body>
   </html>
   ```

### File Structure
Here's what your project structure should look like:
```
my_wasm_project/
├── Cargo.toml
├── src/
│   └── lib.rs
└── index.html
```

### Key Configuration Files
- **`Cargo.toml`**: This file holds your project metadata and dependencies.
- **`src/lib.rs`**: This is your main Rust source file, where you'll define WebAssembly functions.
- **`index.html`**: This HTML file is used to load and test the WebAssembly module.

### Advanced Options
Looking to take it further? Here are some advanced options:

- **Optimizations**: Use the `--release` flag when building for an optimized output:
  ```bash
  wasm-pack build --target web --release
  ```
- **Memory Management**: Make the most of `wasm-bindgen` features for handling memory effectively.

### Troubleshooting
If you run into issues, here are some tips:

- **Build Errors**: Double-check that all dependencies are listed correctly in `Cargo.toml` and that `wasm-pack` is installed.
- **JavaScript Errors**: Look at the console for errors related to module imports or function calls, and ensure the paths in your HTML file are accurate.
- **Performance Issues**: Use your browser's developer tools to profile your WebAssembly code and spot any bottlenecks.

### Best Practices
Keep these practices in mind:

- **Modular Code**: Structure your Rust code modularly for easier maintenance and testing.
- **Documentation**: Add comments to your Rust functions and keep a README to explain your project.
- **Testing**: Write tests for your Rust code using the built-in testing framework.

### Performance Tuning and Workflow Tips
Want to enhance your workflow? Here are some suggestions:

- **Use `wasm-opt`**: This tool helps reduce the size of your WebAssembly binary after building:
  ```bash
  wasm-opt -Oz target/wasm32-unknown-unknown/release/my_wasm_project.wasm -o optimized.wasm
  ```
- **Hot Reloading**: Consider using tools like `webpack` or `parcel` to enable live reloading during development.
- **Code Splitting**: Think about breaking your WebAssembly code into smaller modules to speed up load times.