rust-deps

name	rust-deps
description	Rust dependency management and Cargo.toml configuration. Activates for dependency selection, feature flags, version management, workspace dependencies, publishing, and Cargo.toml questions.

Rust Dependencies Skill

Cargo.toml Best Practices

Edition & MSRV

[package]
edition = "2024"
rust-version = "1.85"

Dependency Specification

[dependencies]
serde = { version = "1.0", features = ["derive"] }   # With features
tokio = { version = "1", features = ["full"] }
log = "0.4"                                            # Minimal version

# Optional dependencies
serde_json = { version = "1.0", optional = true }

[features]
default = []
json = ["dep:serde_json"]

Workspace Dependencies (monorepo)

# Root Cargo.toml
[workspace.dependencies]
serde = { version = "1.0", features = ["derive"] }
tokio = { version = "1", features = ["full"] }

# Crate Cargo.toml
[dependencies]
serde = { workspace = true }
tokio = { workspace = true }

Recommended Crates by Category

Essential

Category	Crate	Purpose
Serialization	serde + serde_json	De/serialization framework
Error (lib)	thiserror	Derive Error for library types
Error (app)	anyhow	Flexible application errors
Logging	tracing	Structured, async-aware logging
CLI	clap (derive)	Command-line argument parsing
HTTP client	reqwest	Ergonomic HTTP client
HTTP server	axum	Modular web framework
Async runtime	tokio	Industry-standard async runtime
Database	sqlx	Compile-time checked SQL
Testing	insta	Snapshot testing
Date/time	chrono or time	Date and time handling

Performance

Crate	Purpose
rayon	Parallel iterators
dashmap	Concurrent hashmap
bytes	Efficient byte buffer
smallvec	Stack-allocated small vectors
criterion	Benchmarking framework
compact_str	Optimized small strings

Development

Crate	Purpose
cargo-watch	Auto-rebuild on changes
cargo-expand	Expand macros
cargo-deny	Audit dependencies
cargo-udeps	Find unused dependencies
cargo-hakari	Workspace-hack for build speed

Dependency Audit

# Security audit
cargo audit

# License check
cargo deny check licenses

# Find unused deps
cargo udeps

# Check for outdated deps
cargo outdated

Version Policy

• Pin major version: serde = "1" (accepts 1.x.y)
• Pin minor for stability: tokio = "1.40" (accepts 1.40.x)
• Exact pin for reproducibility: my-crate = "=1.2.3"
• Use cargo update to update within semver range