rust-patterns_skill

Overview

This skill provides production-ready Rust patterns for 2026 focused on ownership, async with Tokio, Axum web services, SQLx and other DB libraries, error handling, CLI tooling, WASM, and PyO3 Python bindings. It targets Rust Edition 2024 and summarizes concrete mental models, anti-patterns, and recipes you can apply directly in projects. The content is practical, opinionated, and oriented toward maintainable, high-performance systems.

How this skill works

The skill distills common patterns into short examples and decision guides: ownership and borrowing analogies, when to use thiserror vs anyhow, Tokio runtime idioms (spawn, select!, spawn_blocking), Axum routing and shared state, and compile-time checked SQLx usage. It also covers concurrency primitives (Arc, Mutex, RwLock, channels, Rayon), Clap v4 for CLIs, PyO3 bindings for Python extensions, and recommended anti-patterns to avoid.

When to use it

• Designing concurrent or async Rust services where avoiding blocking and correct ownership are critical
• Building HTTP APIs with Axum and shared application state
• Choosing between SQLx, Diesel, or SeaORM based on async needs and safety guarantees
• Creating high-performance native extensions for Python with PyO3 or building WASM modules
• Authoring CLI tools with Clap derive API and clear error handling strategies

Best practices

• Prefer references and clear ownership transfers over excessive cloning; document ownership intent in APIs
• Use thiserror for library error types (matchable variants) and anyhow for application-level errors with context
• Avoid sync blocking inside async functions; use tokio::fs or tokio::task::spawn_blocking for heavy I/O
• Favor channels for message-passing patterns; reserve Arc<Mutex> for simple shared state cases
• Enable SQLx compile-time checks during CI and pick the ORM that matches team expectations (raw SQL vs typed query builder)

Example use cases

• Implementing a multi-threaded Axum web server with shared AppState and SQLx-backed handlers
• Converting a CPU-bound Python hotspot to a PyO3 native extension built with maturin
• Building a resilient CLI tool with Clap v4, structured errors via thiserror, and clear exit codes
• Refactoring an async codebase to remove blocking I/O, applying spawn_blocking and Tokio select! for timeouts
• Using Rayon to speed up batch data processing while keeping IO on async tasks