Cargo.toml File — Rust Cargo Manifest

Cargo.toml is the manifest file for Rust projects, used by Cargo — Rust's package manager and build system. The file uses TOML format to define the package's name, version, edition (2015, 2018, 2021), authors, license, and description in the [package] section. Dependencies are listed in [dependencies] with version constraints following semantic versioning, supporting crates.io packages, Git repositories, and local paths. Cargo.toml supports multiple sections: [dev-dependencies] for test/development only packages, [build-dependencies] for build scripts, [features] for conditional compilation, [workspace] for multi-package projects, and [profile] for optimization settings (debug, release, custom profiles). The manifest also configures binary targets, library targets, examples, tests, and benchmarks. Cargo resolves dependencies, downloads packages from crates.io, compiles the project and all dependencies, runs tests, generates documentation, and publishes packages. The companion Cargo.lock file records exact resolved versions for reproducible builds. Cargo's design — combining package management, build system, test runner, and documentation generator — is considered one of the best developer tool experiences in any programming language, consistently praised for its reliability and ergonomics.