ccfg-rust

Autonomous per-module test coverage improvement loop for Rust projects

Initialize a new Rust project with opinionated production-ready defaults

Run Rust quality gates - clippy, fmt, test, deny/audit, with workspace detection

Use for building web APIs and services with axum and tower. Examples: designing REST endpoints, implementing middleware layers, managing shared state with Arc, building WebSocket handlers, writing custom extractors, composing routers, or integrating tower services. Ideal for projects using the axum/tower/hyper/tokio ecosystem.

Use for Rust testing: unit tests with #[cfg(test)], integration tests in tests/, doc tests, property-based testing with proptest, benchmarks with criterion, mocking with mockall, and async tests with #[tokio::test]. Examples: writing comprehensive test suites, setting up proptest strategies, creating criterion benchmarks, mocking trait dependencies, or building test fixtures with builders.

Use for modern Rust 2021+ development: ownership/borrowing, traits, generics, error handling with thiserror/anyhow, macros, unsafe code, iterators, and concurrency primitives. Examples: designing type-safe APIs, implementing trait hierarchies, building zero-cost abstractions, refactoring to eliminate clones, writing custom derive macros, or auditing unsafe code blocks.

Use for async Rust development with tokio: runtime configuration, futures, streams, channels, task management, select!, graceful shutdown, and concurrent patterns. Examples: building async services, implementing fan-out/fan-in pipelines, managing connection pools, coordinating concurrent tasks with JoinSet, or debugging async deadlocks and cancellation issues.

This skill should be used when managing Cargo.toml configuration, workspace setup, dependency management, feature flags, publishing crates, or configuring build profiles in Rust projects.

This skill should be used when working on Rust projects, writing Rust code, running Rust tests, managing Cargo dependencies, or reviewing Rust code.

This skill should be used when writing tests for Rust code, running cargo test, setting up test infrastructure, or reviewing test quality in Rust projects.