rust-script

name	rust-script
description	Use when writing any standalone Rust script, one-off utility, or when tempted to reach for a shell script with complex logic. Covers rust-script shebang, inline Cargo manifest, and dependency declaration.

The Pattern

#!/usr/bin/env rust-script
//! ```cargo
//! [dependencies]
//! anyhow = "1"
//! ```

fn main() -> anyhow::Result<()> {
    println!("hello");
    Ok(())
}

Run with: rust-script script.rs or just ./script.rs (if chmod +x)

No-Dependency Script

#!/usr/bin/env rust-script

fn main() {
    println!("hello");
}

Common Packages (copy-paste ready)

Package	Use
anyhow	Error handling
clap	CLI argument parsing
serde + serde_json	JSON parsing
reqwest	HTTP (blocking feature)
tokio	Async runtime
colored	Terminal color output
indicatif	Progress bars

Async Script

#!/usr/bin/env rust-script
//! ```cargo
//! [dependencies]
//! tokio = { version = "1", features = ["full"] }
//! reqwest = "0.12"
//! ```

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let body = reqwest::get("https://example.com").await?.text().await?;
    println!("{body}");
    Ok(())
}

Installation

cargo install rust-script
# or via mise
mise use -g rust-script

Script vs Tool Decision

Need	Use
Transform JSON	jq
Quick calc / string	shell arithmetic or awk
Complex logic, Rust types	rust-script
Reusable binary	proper cargo new project
Never use for scripts	cargo run in a throwaway project

Notes

• First run compiles and caches — subsequent runs are fast
• Cache lives at ~/.cache/rust-script/
• cargo -Zscript (RFC 3424) is the future stable path but still nightly-only as of 2026