The m03-mutability skill diagnoses and resolves Rust mutability errors (E0596, E0499, E0502) by guiding developers to understand whether mutation is architecturally necessary and which mutability pattern fits their use case—from simple `&mut T` borrows to interior mutability types like `Cell`, `RefCell`, and `Mutex`. It serves Rust developers debugging borrow checker conflicts by transforming "add mut" impulses into design questions, then tracing issues upward to data structure problems or downward to the appropriate implementation pattern. The skill solves the common problem of developers treating mutability as a tactical syntax issue rather than a design decision about ownership and access control.
npx skills add https://github.com/zhanghandong/rust-skills --skill m03-mutability