Cargo vs opam
Cargo
doc.rust-lang.orgopam
opam.ocaml.orgSide by side
| Figure | Cargo | opam |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Plans published | 1 | 0 |
| Spec score · Package Managers | 8.8 (#6) | 7.6 (#63) |
| Dependency resolution | Yes | Yes |
| Free plan | Yes | Yes |
| Lockfile support | Yes | Yes |
| Offline installation | Yes | Yes |
| Package formats | Rust crates; crates.io packages; alternate registry packages; Git dependencies; local path dependencies | opam package definition files and archives |
| Purpose | Cargo is the Rust package manager. | opam is a source-based package manager for OCaml. |
| Support | Cargo asks users to report bugs through its GitHub issue tracker. | Bug reports and feature requests go to opam's issue tracker; general queries can be addressed on the OCaml-platform mailing list. |
| Supported platforms | Windows; macOS; Linux; other Unix-like systems | Linux,macOS,FreeBSD,OpenBSD,NetBSD,Windows |
| Supported systems | Rustup installation instructions cover Windows, macOS, Linux, and other Unix-like systems, and Cargo is included in the Rust toolchain. | The install guide lists precompiled binaries for Linux, macOS, FreeBSD, OpenBSD, NetBSD, and Windows. |
Plans
In their own words
Cargo
Cargo is the free package manager and build tool for Rust, used through a command-line interface. It downloads dependencies, builds packages, and supports repeatable builds with lockfiles. Developers can compile, check, document, test, run, package, install, and publish Rust projects. The `cargo new` command creates a package, defaulting to a binary; adding `--lib` creates a library. Cargo uses crates.io by default and also handles alternate registries, Git dependencies, and local paths. Workspaces allow multiple packages to share a lockfile and output directory. Package features can enable conditional compilation and optional dependencies. In offline mode, Cargo avoids network access and attempts to use cached data. It supports authentication options for registries and new subcommands without modifying Cargo itself. Rustup installs Cargo with the stable Rust release, and installation instructions cover Windows, macOS, Linux, and other Unix-like systems. Cargo is open source under the MIT and Apache License, Version 2.0. Some documented capabilities remain unstable and require a nightly toolchain and `-Z` flags.