Cargo

Cargo is Rust’s build system and package manager.

Quick links:

• Crate registry

Building

Cargo’s build system assumes that source files are in the src folder, and the executable will be created in the target folder (/debug by default, /release in release mode).

The Cargo.toml file specifies which dependencies projects rely on and has fuzzy version numbers (i.e., it works with what is compatible with your code).

The Cargo.lock file ensures project builds are reproducible. It essentially functions as a requirements.txt that manages package conflicts.

CLI commands

Assume commands are prefixed with cargo.

• build: to build an application, by default in debug mode.
  • --release: to compile with optimisations in release mode.
• run: to run the executable.
• check: to make sure it compiles (but doesn’t product an executable).
• update: figures out the latest versions that match the specifications in Cargo.toml, ignoring the Cargo.lock file.