rust-skills

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkDeclared1 observation
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

AGENTS.md

CLAUDE.md

Audit 0.4.1 · source sha 7bf456ca5b06 · 20 Oct 2026Report an issue or request a re-scan

• Publisherleonardomso GitHub userOwner of the repository this skill is read from
• Source folderleonardomso/rust-skillsThe exact folder we audited
• LicenceMITAs the repository states it
• Commit pinned for this verdict7bf456ca5b06A new audit runs when the source changes
• Repository statusNot archivedLast push 127 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Comprehensive Rust coding guidelines with 265 rules across 26 categories. Use when writing, reviewing, or refactoring Rust code. Covers ownership, error handling, async patterns, concurrency, unsafe code, API design,…

---
name: rust-skills
description: >
  Comprehensive Rust coding guidelines with 265 rules across 26 categories.
  Use when writing, reviewing, or refactoring Rust code. Covers ownership,
  error handling, async patterns, concurrency, unsafe code, API design, memory
  optimization, performance, numeric safety, conversions, serde, pattern
  matching, macros, closures, observability, testing, and common anti-patterns.
  Invoke with /rust-skills.
license: MIT
metadata:
  author: leonardomso
  version: "1.5.1"
  sources:
    - Rust API Guidelines
    - Rust Performance Book
    - Rust 2024 Edition Guide
    - The Rustonomicon
    - ripgrep, tokio, serde, polars, axum, cargo codebases
---

# Rust Best Practices

Comprehensive guide for writing high-quality, idiomatic, and highly optimized Rust code. Contains 265 rules across 26 categories, prioritized by impact to guide LLMs in code generation and refactoring. Current for Rust 1.96 (2024 edition).

## When to Apply

Reference these guidelines when:
- Writing new Rust functions, structs, or modules
- Implementing error handling or async code
- Writing concurrent, parallel, or `unsafe` code
- Designing public APIs for libraries
- Reviewing code for ownership/borrowing issues
- Optimizing memory usage or reducing allocations
- Tuning performance for hot paths
- Refactoring existing Rust code

## Rule Categories by Priority

| Priority | Category | Impact | Prefix | Rules |
|----------|----------|--------|--------|-------|
| 1 | Ownership & Borrowing | CRITICAL | `own-` | 12 |
| 2 | Error Handling | CRITICAL | `err-` | 12 |
| 3 | Memory Optimization | CRITICAL | `mem-` | 17 |
| 4 | Unsafe Code | CRITICAL | `unsafe-` | 7 |
| 5 | API Design | HIGH | `api-` | 17 |
| 6 | Async/Await | HIGH | `async-` | 18 |
| 7 | Concurrency | HIGH | `conc-` | 4 |
| 8 | Compiler Optimization | HIGH | `opt-` | 12 |
| 9 | Numeric & Arithmetic Safety | HIGH | `num-` | 5 |
| 10 | Type Safety | MEDIUM | `type-` | 13 |
| 11 | Trait & Generics Design | MEDIUM | `trait-` | 6 |
| 12 | Conversions | MEDIUM | `conv-` | 3 |
| 13 | Const & Compile-Time | MEDIUM | `const-` | 4 |
| 14 | Serde | MEDIUM | `serde-` | 8 |
| 15 | Pattern Matching | MEDIUM | `pat-` | 5 |
| 16 | Macros | MEDIUM | `macro-` | 8 |
| 17 | Closures | MEDIUM | `closure-` | 5 |
| 18 | Collections | MEDIUM | `coll-` | 4 |
| 19 | Naming Conventions | MEDIUM | `name-` | 16 |
| 20 | Testing | MEDIUM | `test-` | 15 |
| 21 | Documentation | MEDIUM | `doc-` | 12 |
| 22 | Observability | MEDIUM | `obs-` | 7 |
| 23 | Performance Patterns | MEDIUM | `perf-` | 13 |
| 24 | Project Structure | LOW | `proj-` | 14 |
| 25 | Clippy & Linting | LOW | `lint-` | 13 |
| 26 | Anti-patterns | REFERENCE | `anti-` | 15 |

---

## Quick Reference

### 1. Ownership & Borrowing (CRITICAL)

- [`own-borrow-over-clone`](rules/own-borrow-over-clone.md) - Prefer `&T` borrowing over `.clone()`
- [`own-slice-over-vec`](rules/own-slice-over-vec.md) - Accept `&[T]` not `&Vec<T>`, `&str` not `&String`
- [`own-cow-conditional`](rules/own-cow-conditional.md) - Use `Cow<'a, T>` for conditional ownership
- [`own-arc-shared`](rules/own-arc-shared.md) - Use `Arc<T>` for thread-safe shared ownership
- [`own-rc-single-thread`](rules/own-rc-single-thread.md) - Use `Rc<T>` for shared ownership in single-threaded contexts
- [`own-refcell-interior`](rules/own-refcell-interior.md) - Use `RefCell<T>` for interior mutability in single-threaded code
- [`own-mutex-interior`](rules/own-mutex-interior.md) - Use `Mutex<T>` for interior mutability across threads
- [`own-rwlock-readers`](rules/own-rwlock-readers.md) - Use `RwLock<T>` when reads significantly outnumber writes
- [`own-copy-small`](rules/own-copy-small.md) - Implement `Copy` for small, simple types
- [`own-clone-explicit`](rules/own-clone-explicit.md) - Use explicit `Clone` for types where copying has meaningful cost
- [`own-move-large`](rules/own-move-large.md) - Move large types instead of copying; use `Box` if moves are expensive
- [`own-lifetime-elision`](rules/own-lifetime-elision.md) - Rely on lifetime elision rules; add explicit lifetimes only when required

### 2. Error Handling (CRITICAL)

- [`err-thiserror-lib`](rules/err-thiserror-lib.md) - Use `thiserror` for library error types
- [`err-anyhow-app`](rules/err-anyhow-app.md) - Use `anyhow` for application error handling
- [`err-result-over-panic`](rules/err-result-over-panic.md) - Return `Result<T, E>` instead of panicking for recoverable errors
- [`err-context-chain`](rules/err-context-chain.md) - Add context with `.context()` or `.with_context()`
- [`err-no-unwrap-prod`](rules/err-no-unwrap-prod.md) - Avoid `unwrap()` in production code; use `?`, `expect()`, or handle errors
- [`err-expect-bugs-only`](rules/err-expect-bugs-only.md) - Use `expect()` only for invariants that indicate bugs, not user errors
- [`err-question-mark`](rules/err-question-mark.md) - Use `?` operator for clean propagation
- [`err-from-impl`](rules/err-from-impl.md) - Implement `From<E>` for error conversions to enable `?` operator
- [`err-source-chain`](rules/err-source-chain.md) - Preserve error chains with `#[source]` or `source()` method
- [`err-lowercase-msg`](rules/err-lowercase-msg.md) - Start error messages lowercase, no trailing punctuation
- [`err-doc-errors`](rules/err-doc-errors.md) - Document error conditions with `# Errors` section in doc comments
- [`err-custom-type`](rules/err-custom-type.md) - Define custom error types for domain-specific failures

### 3. Memory Optimization (CRITICAL)

- [`mem-with-capacity`](rules/mem-with-capacity.md) - Use `with_capacity()` when size is known
- [`mem-smallvec`](rules/mem-smallvec.md) - Use `SmallVec` for usually-small collections
- [`mem-arrayvec`](rules/mem-arrayvec.md) - Use `ArrayVec<T, N>` for fixed-capacity collections that never heap-allocate
- [`mem-box-large-variant`](rules/mem-box-large-variant.md) - Box large enum variants to reduce overall enum size
- [`mem-boxed-slice`](rules/mem-boxed-slice.md) - Use `Box<

Excerpt, first 6,000 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

1. 2026-10-20
   ✓SAFE B 89 / 100

   first audit · source 7bf456ca5b06

Questions about rust-skills

• github.com/leonardomso/rust-skills — the audited source at commit 7bf456ca5b06 and every finding aboveObserved · 20 Oct 2026

Spotted something wrong? Report a correction · Methodology