Chapter 2: Getting Started

This chapter guides you through setting up your Rust development environment and writing your first program. By the end, you'll have a fully configured workspace and understand the basics of Cargo, Rust's build system and package manager.

2.1 Installing Rust

Rust is installed through rustup, the official Rust toolchain installer. It manages Rust versions and associated tools, making it easy to keep your installation up to date.

macOS and Linux

Open your terminal and run:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

This command downloads and runs the rustup installer. Follow the on-screen prompts (usually pressing Enter for default options is fine).

source "$HOME/.cargo/env"

source ~/.cargo/env

Windows

Verifying the Installation

After installation, verify everything works:

# Check Rust compiler version
rustc --version
# Example output: rustc 1.75.0 (82e1608df 2023-12-21)

# Check Cargo version
cargo --version
# Example output: cargo 1.75.0 (1d8b05cdd 2023-11-20)

# Check rustup version
rustup --version
# Example output: rustup 1.26.0 (5af9b9484 2023-04-05)

2.2 Updating and Managing Rust

Rust releases a new stable version every six weeks. Keep your installation current:

# Update Rust to the latest version
rustup update

# Show installed toolchains
rustup show

# Install a specific version
rustup install 1.70.0

# Switch default toolchain
rustup default stable

# Install nightly (for experimental features)
rustup install nightly
rustup run nightly cargo build

2.3 IDE Setup

A good IDE makes Rust development much more productive. We recommend Visual Studio Code with the rust-analyzer extension.

Visual Studio Code Setup

What rust-analyzer Provides

Other IDE Options

• IntelliJ IDEA + Rust plugin: Full IDE experience, great for large projects
• CLion + Rust plugin: JetBrains IDE with native debugging
• Neovim + rust-tools.nvim: For terminal-based workflows
• Helix: Modern terminal editor with built-in Rust support

2.4 Your First Rust Program

Let's create and run your first Rust program using Cargo.

Creating a New Project

# Create a new project called hello_rust
cargo new hello_rust

# Navigate into the project
cd hello_rust

Cargo creates this project structure:

Understanding Cargo.toml

Open Cargo.toml - this is your project's manifest:

[package]
name = "hello_rust"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at
# https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
# Your external dependencies go here

The Main File

Open src/main.rs:

fn main() {
    println!("Hello, world!");
}

Let's break this down:

Running the Program

# Build and run
cargo run

# Output:
   Compiling hello_rust v0.1.0 (/path/to/hello_rust)
    Finished dev [unoptimized + debuginfo] target(s) in 0.42s
     Running `target/debug/hello_rust`
Hello, world!

2.5 Understanding Cargo Commands

Cargo is your constant companion in Rust development. Here are the essential commands:

Debug vs Release Builds

# Debug build (fast compilation, slow execution, with debug symbols)
cargo build
# Binary: target/debug/hello_rust

# Release build (slow compilation, fast execution, optimized)
cargo build --release
# Binary: target/release/hello_rust

2.6 Adding Dependencies

Rust's package ecosystem lives on crates.io. Let's add a dependency:

# Add the rand crate
cargo add rand

This updates your Cargo.toml:

[dependencies]
rand = "0.8.5"

Now use it in your code:

use rand::Rng;

fn main() {
    let secret_number = rand::thread_rng().gen_range(1..=100);
    println!("Secret number: {}", secret_number);
}

Understanding Version Numbers

2.7 Project Structure Best Practices

As your project grows, organize it properly:

Library vs Binary Crates

# Create a library project
cargo new my_library --lib

# Create a binary project (default)
cargo new my_app

2.8 Chapter Summary

2.9 Review Questions

2.10 Looking Ahead