cargo

Development

Use when working with the cargo CLI — Rust's package manager. Covers the manifest format (Cargo.toml), dependencies, features, workspaces, build profiles, build scripts, configuration (.cargo/config.toml), registries and publishing, environment variables, the lockfile and cache, and the command reference. Triggers on: "cargo", "cargo build", "cargo check", "cargo test", "cargo run", "cargo add", "cargo update", "cargo publish", "cargo new", "cargo init", "cargo install", "cargo doc", "cargo bench", "cargo tree", "cargo metadata", "Cargo.toml", "Cargo.lock", "crate", "workspace", "feature", "profile", "build script", "build.rs", "registry", "crates.io", "CARGO_HOME", "rustc", "rustdoc", "rust-version", "edition".

QUICK START

How to use this skill

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Cargo — Rust's Package Manager In-Depth Reference

Comprehensive reference for the cargo CLI (https://doc.rust-lang.org/cargo/), covering the manifest format, dependency specification, the features system and resolver, workspaces, build profiles, build scripts, configuration, registries and publishing, environment variables, the lockfile and cache layout, and the full command reference.

Data Flow

Cargo.toml (manifest)
  → dependency resolver (registry index + Cargo.lock)
    → fetch (registry cache / git / path / vendor)
      → build scripts (build.rs, OUT_DIR)
        → rustc / rustdoc (per profile, per target)
          → target/<profile>/  (artifacts)
            → run / test / bench / install

Sub-Resources

Load the reference that matches your task. When in doubt, load multiple references.

Keywords	Reference
concept, package, crate, target, binary, library, example, test, bench, edition, registry, Cargo.toml, Cargo.lock, cargo home, build pipeline, crate types, cdylib, rlib, dylib, staticlib, proc-macro, target triple, host vs target, cross-compilation, manifest vs lockfile	references/concepts.md
manifest, Cargo.toml, `[package]`, name, version, edition, rust-version, authors, description, license, license-file, keywords, categories, readme, homepage, repository, documentation, metadata, publish, include, exclude, build, links, default-run, resolver, autolib, autobins, autoexamples, autotests, autobenches, `[lib]`, `[[bin]]`, `[[example]]`, `[[test]]`, `[[bench]]`, crate-type, required-features, doctest, `[lints]`, `[badges]`, cargo-features	references/manifest.md
dependency, [dependencies], [dev-dependencies], [build-dependencies], [target.*.dependencies], version requirement, SemVer, caret requirement, tilde requirement, wildcard, git dependency, branch, tag, rev, path dependency, registry dependency, optional dependency, default-features, features, rename, package, workspace dependency, dependency inheritance, platform-specific, cfg expression	references/dependencies.md
feature, [features], default, dep: syntax, optional dependency as feature, package/feature, weak dependency, ?/ syntax, feature unification, additive, mutually exclusive, resolver v1, resolver v2, resolver v3, --features, --all-features, --no-default-features, required-features, CARGO_FEATURE, feature inspection, cargo tree -e features, SemVer compatibility	references/features.md
workspace, [workspace], members, exclude, virtual manifest, default-members, resolver, workspace.package, workspace.dependencies, workspace inheritance, workspace metadata, root package, shared target directory, path dependencies in workspace	references/workspaces.md
profile, [profile.dev], [profile.release], [profile.test], [profile.bench], opt-level, debug, debug-assertions, overflow-checks, lto, panic, incremental, codegen-units, rpath, strip, split-debuginfo, inherits, custom profile, --profile, --release, package override, build-override, unit graph, target directory layout, monomorphization, generics	references/profiles.md
build script, build.rs, build dependency, [build-dependencies], links, *-sys, OUT_DIR, cargo::rustc-link-lib, cargo::rustc-link-search, cargo::rustc-flags, cargo::rustc-cfg, cargo::rustc-check-cfg, cargo::rustc-env, cargo::rerun-if-changed, cargo::rerun-if-env-changed, cargo::warning, cargo::error, cargo::metadata, DEP_, jobserver, code generation, override build script, build script env vars	references/build-scripts.md
config, configuration, .cargo/config.toml, config hierarchy, precedence, --config, environment variable mapping, CARGO_ prefix, [build], [target], [registry], [source], [net], [http], [term], [env], [alias], [cargo-new], [profile], [credential-alias], [future-incompat-report], [cache], credentials.toml, credential provider, include, rustflags, rustdocflags, rustc-wrapper, target-dir, jobs, proxy, timeout	references/config.md
registry, crates.io, index, git protocol, sparse protocol, sparse+, config.json, authentication, token, credential provider, cargo:token, cargo:wincred, cargo:macos-keychain, cargo:libsecret, cargo login, cargo logout, cargo owner, cargo yank, cargo publish, cargo search, cargo info, custom registry, alternate registry, source replacement, replace-with, [patch], [replace], local registry, directory source, vendor, cargo vendor, publish restriction	references/registries.md
command, subcommand, flag, cargo build, cargo check, cargo test, cargo bench, cargo run, cargo doc, cargo clean, cargo fix, cargo rustc, cargo rustdoc, cargo add, cargo remove, cargo update, cargo tree, cargo metadata, cargo vendor, cargo fetch, cargo new, cargo init, cargo install, cargo uninstall, cargo search, cargo info, cargo login, cargo logout, cargo owner, cargo yank, cargo publish, cargo package, cargo pkgid, cargo locate-project, cargo generate-lockfile, cargo report, cargo config, cargo version, common flags, --manifest-path, --locked, --frozen, --offline, -Z, pkgid spec, message-format, timings	references/commands.md
environment variable, CARGO_HOME, CARGO_BIN_NAME, CARGO_BUILD_, CARGO_CFG_TARGET_, CARGO_CRATE_NAME, CARGO_ENCODED_RUSTFLAGS, CARGO_ENCODED_RUSTDOCFLAGS, CARGO_INCREMENTAL, CARGO_MANIFEST_DIR, CARGO_MANIFEST_LINKS, CARGO_NET_, CARGO_PKG_, CARGO_REGISTRY_, CARGO_TARGET_DIR, CARGO_TARGET_TMPDIR, CARGO_TERM_, CARGO_LOG, CARGO_MAKEFLAGS, RUSTFLAGS, RUSTDOCFLAGS, RUSTC, RUSTDOC, RUSTC_WRAPPER, [env] config, force, relative	references/environment.md
lockfile, Cargo.lock, lockfile format, package ID, source id, checksum, lockfile version, v3, v4, commit, generate-lockfile, update, precise, dry-run, breaking, cache, registry cache, git cache, ~/.cargo, target directory, target/debug, target/release, fingerprint, incremental, auto-clean	references/lockfile.md

Quick Guide

What are cargo's core concepts? → references/concepts.md
How do I write Cargo.toml? → references/manifest.md
How do I specify dependencies? → references/dependencies.md
How do features and the resolver work? → references/features.md
How do workspaces work? → references/workspaces.md
How do build profiles work? → references/profiles.md
How do I write a build script? → references/build-scripts.md
How does cargo configuration work? → references/config.md
How do registries and publishing work? → references/registries.md
What commands does cargo have? → references/commands.md
What environment variables does cargo use? → references/environment.md
How does Cargo.lock work? → references/lockfile.md
How do I add a dependency? → references/dependencies.md and references/commands.md
How do I enable features? → references/features.md and references/commands.md
How do I configure rustc flags? → references/config.md and references/environment.md
How do I publish to crates.io? → references/registries.md
How do I vendor dependencies? → references/registries.md and references/commands.md
How do I override a dependency? → references/registries.md ([patch], source replacement)
How do I inspect the dependency graph? → references/commands.md (cargo tree, cargo metadata)
How do I set up a custom registry? → references/config.md and references/registries.md
How do I do reproducible builds? → references/lockfile.md and references/commands.md (--locked, --frozen)

Cross-Project References

For the rustc and rustdoc compilers themselves (flag reference, codegen options, lint catalog, target specs), see the official rustc book and rustdoc book — this skill covers only how cargo invokes them.
For the Rust language (editions, attributes, cfg expressions, macros, the reference), see the Rust Reference.
For carapace-specific cargo completion (the cargo completer, macros like tools.cargo.*), see the carapace skill (in this repo) → references/spec.md within that skill.