rust-systems

rust-systems is a skill for Claude Code, Codex from FutureJJ/claude-skills. It costs 64 tokens per session (290 once invoked), scanned A, original, MIT.

Guidance for Rust systems programming, including memory ownership, asynchronous code, traits, low-level interfaces, and error handling.

In plain words
What is it for?
Resolving ownership and lifetime errors, designing traits and enums, writing async Rust, handling errors, working with unsafe code or foreign-function interfaces, and using pattern matching.
Why use it?
It helps write Rust that satisfies the borrow checker while remaining safe, efficient, and maintainable.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/futurejj/claude-skills/rust-systems
Any agent
npx skills add FutureJJ/claude-skills --skill rust-systems
Clone the repo
git clone --depth 1 https://github.com/FutureJJ/claude-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for rust-systems

README.md
[![agentmods](https://agentmods.dev/badge/skills/futurejj/claude-skills/rust-systems.svg)](https://agentmods.dev/skills/futurejj/claude-skills/rust-systems)
Your own site
<a href="https://agentmods.dev/skills/futurejj/claude-skills/rust-systems"><img src="https://agentmods.dev/badge/skills/futurejj/claude-skills/rust-systems.svg" alt="Measured on agentmods" height="20"></a>
Per session 64 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 290 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00064 $0.00290
Opus 5 $0.00032 $0.00145
Sonnet 5 $0.00013 $0.00058
Haiku 4.5 $0.00006 $0.00029

Measured 6d ago against content hash 9978371fff23, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

rust-systems scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/rust-systems/SKILL.md · 30 lines

What it actually says

Rust Systems Engineer

You are a Rust expert who helps developers write safe, performant, and idiomatic Rust.

Core Principles

  • Ownership is your friend. The borrow checker prevents data races and use-after-free.
  • Enums for state. Rust enums with data replace inheritance hierarchies.
  • Error handling with Result. Use thiserror for libraries, anyhow for applications.
  • Zero-cost abstractions. Iterators, generics, traits compile to efficient machine code.

Anti-Patterns

  • .clone() everywhere — restructure ownership instead
  • .unwrap() in production — use ? or explicit handling
  • Box<dyn Trait> when generics work — dynamic dispatch has cost
  • Premature unsafe — most problems have safe solutions

Reference Guide

Topic Reference Load When
Ownership & borrowing references/ownership.md Borrow checker errors, lifetimes
Async Rust references/async-rust.md Tokio, async traits, pinning
Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 30 lines · 64 tokens per session scan A 9978371fff23

Subscribe to this mod's changes

rust-systems is a skill published in the GitHub repository FutureJJ/claude-skills (3 stars, last pushed 6mo ago), licensed MIT. It adds 64 tokens to every session and 290 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

neo-rust

Use this skill when writing, refactoring, debugging, or auditing Rust code. Trigger for .rs files, Cargo projects, ownership/borrowing/lifetime issues, Result/Option error handling, unnecessary clone/performance work, unsafe code review, or modern Rust architecture.

Benknightdark/neo-skills · 58 tokens

kaspa-sovereign-architect-engine

Source-grounded Kaspa protocol and Toccata engineering for Rusty Kaspa, KIPs, wallets, Kasware/Kaspium, indexers, WASM/TypeScript, covenants, ZK, vProgs, mining, infrastructure, repository audits, and current network or release status. Use when Codex must research, explain, design, implement, review, or verify Kaspa…

gryszzz/Kaspa-Ai-Agent-Skill · 114 tokens

swift-networking

Builds a protocol-based async/await networking layer with URLSession, testable abstractions, error handling, and mock support for Swift projects. Use when user says "add networking", "create an API layer", "fetch data from API", "build a network service", "add URLSession", "implement HTTP requests", "create a REST…

jeremieb/swift-unit-test-instructions · 82 tokens

swift-project-setup

Bootstraps a new Swift/SwiftUI/UIKit project with MVVM architecture, standard folder structure, testing targets, and CLAUDE.md configuration. Use when user says "create a new project", "setup a new app", "start a new iOS project", "scaffold a Swift project", "initialize an Xcode project", or "new SwiftUI app".

jeremieb/swift-unit-test-instructions · 80 tokens

polars

High-performance DataFrame library for Python ETL, analytics, and pandas migration. Use for expression-based data manipulation with lazy query optimization, parallel execution, streaming out-of-core processing, Arrow interoperability, and optional GPU execution.

K-Dense-AI/scientific-agent-skills · 47 tokens

rust-engineer

Writes, reviews, and debugs idiomatic Rust code with memory safety and zero-cost abstractions. Implements ownership patterns, manages lifetimes, designs trait hierarchies, builds async applications with tokio, and structures error handling with Result/Option. Use when building Rust applications, solving ownership or…

Jeffallan/claude-skills · 120 tokens