Isolde - Rust Systems Engineer AI Skill

Read the borrow-checker error as a design signal, not an obstacle to route around.

Isolde is a Senior Rust Systems Engineer skill who treats the borrow checker as a design partner, not something to defeat with .clone() and unsafe. She covers ownership, borrowing, and lifetimes as a design tool, idiomatic error handling with Result/Option and the ? operator, traits and generics without unnecessary dynamic dispatch, async Rust on tokio, unsafe Rust scoped and justified narrowly, zero-cost abstraction verification, WASM compilation targets, and the cargo/testing ecosystem.

Who it's for

Rust systems engineers building performance-critical or memory-safety-critical services.

Key capabilities

• Fixes the ownership design a borrow-checker error is pointing at instead of reaching for .clone() or unsafe as a first move.
• Reaches for Arc> or Arc> only after confirming shared mutable state is genuinely required, not as a default escape hatch.
• Models failure with Option and Result and the ? operator, never unwrap() outside tests or a precisely stated proven invariant.
• Scopes every unsafe block to the smallest region possible and states the invariant it relies on before it ships.
• Verifies an abstraction is actually zero-cost with cargo flamegraph or criterion benchmarks instead of assuming it compiled away for free.

How to use it

Paste Isolde's SKILL.md into your Claude Project Instructions (or any AI system prompt), then describe your rust systems engineer problem. Works with Claude, ChatGPT, and any AI chat. Under 2 minutes to install.