> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gcore.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Set up Rust for FastEdge
The Modern Rust SDK is the recommended approach for new FastEdge HTTP applications. It is based on [WASI-HTTP](https://github.com/WebAssembly/WASI), the standard WebAssembly interface for HTTP applications, and uses the `wstd` crate, which provides Rust bindings for WASI-HTTP.
[Rust and Cargo](https://rustup.rs) are required. On Windows, also install [Visual Studio Build Tools](https://visualstudio.microsoft.com/downloads/#build-tools-for-visual-studio-2022) with the **Desktop development with C++** workload.
Existing apps built with the `fastedge` crate and `wasm32-wasip1` use a different setup — covered in the [Legacy Rust](/fastedge/getting-started/setup-rust-legacy) guide.
## Add the WebAssembly target
FastEdge runs applications compiled to `wasm32-wasip2`. Add the target once — it applies to all future builds:
```sh theme={null}
rustup target add wasm32-wasip2
```
## Configure a project
FastEdge applications compile to WebAssembly libraries rather than standalone executables, so start with a Rust library project. Two changes from the defaults are needed: the output type must be `cdylib` (a format the WASI runtime can load), and `wstd` must be listed as a dependency.
1. Create the library crate:
```sh theme={null}
cargo new --lib my-app
cd my-app
```
2. Replace the contents of `Cargo.toml`:
```toml theme={null}
[package]
name = "my_app"
version = "0.1.0"
edition = "2021"
[lib]
crate-type = ["cdylib"]
[dependencies]
wstd = "0.6"
anyhow = "1"
```
Without `crate-type = ["cdylib"]`, the build succeeds but the output can't run as a FastEdge application.
## Verify the toolchain
A minimal handler is enough to confirm the toolchain produces a valid WebAssembly component. Replace `src/lib.rs`:
```rust theme={null}
use wstd::http::body::Body;
use wstd::http::{Request, Response};
#[wstd::http_server]
async fn main(_request: Request) -> anyhow::Result> {
Ok(Response::builder()
.status(200)
.body(Body::from("OK"))?)
}
```
Build it:
```sh theme={null}
cargo build --release --target wasm32-wasip2
```
The first build downloads dependencies and takes one to two minutes. When it completes without errors, the toolchain is ready — the compiled binary is at `./target/wasm32-wasip2/release/my_app.wasm`.