Rust Development

This skill covers Rust development with two specialized reference documents:

When Starting a New Project

Use Rust-Project-Setup.md for:

• •Creating new Rust CLI/TUI applications from scratch
• •Cargo.toml setup and dependency selection
• •Module structure and organization
• •System dependency documentation (ALSA, X11, OpenGL, etc.)
• •Configuration with serde/toml
• •README and documentation templates
• •Step-by-step implementation workflow

When Writing Code

Use Rust-Patterns.md for:

• •Trait-based abstractions for swappable implementations
• •Typestate pattern for security-sensitive state machines (compile-time state enforcement)
• •Error handling (anyhow vs thiserror)
• •CLI argument parsing with clap
• •Structured logging with tracing
• •Frame timing and performance monitoring
• •Linux device I/O (v4l2, video processing)
• •Color space conversion (RGB to YUYV)
• •Testing patterns with mocks
• •Defensive programming patterns

Quick Reference

Error Handling Decision

Is this a library?
├─ Yes → Use thiserror for typed errors
└─ No (application) → Use anyhow with .context()

State Machine Decision

Is this security-sensitive? (auth, crypto, transactions)
├─ Yes → Use TYPESTATE pattern (compile-time enforcement)
│        - State encoded in type system
│        - Invalid transitions = compile errors
│        - Methods only exist for valid states
└─ No → Runtime enums are fine
         - UI state, display modes
         - States that need runtime inspection

Common Dependencies

Cargo Commands

cargo check          # Fast compilation check
cargo build          # Debug build
cargo build --release # Optimized build
cargo test           # Run tests
cargo clippy         # Lint code
cargo fmt            # Format code
cargo doc --open     # Generate docs

Cargo.lock Decision

• •Applications/Binaries: Commit Cargo.lock (reproducible builds)
• •Libraries: Don't commit (let downstream decide versions)