# Rust Dev

> This skill should be used when working with Rust code, reviewing Rust code, managing Rust dependencies, creating Rust projects, or fixing Rust compilation errors. It provides strict coding standards (especially FAIL FAST error handling), workspace architecture guidance, dependency management automation, and common Rust patterns.

- **Type:** Skill
- **Install:** `agentstack add skill-onsails-cc-rust-dev`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [onsails](https://agentstack.voostack.com/s/onsails)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [onsails](https://github.com/onsails)
- **Source:** https://github.com/onsails/cc/tree/master/rust-dev/skills/rust-dev

## Install

```sh
agentstack add skill-onsails-cc-rust-dev
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Rust Development

## Workflow

For any non-trivial Rust change:

1. **Discover project guidelines** — Read `CLAUDE.md`, `AGENTS.md` (in repo root and `.claude/`, `.cursor/`, `.codex/` subdirs), `rustfmt.toml`, `clippy.toml`, `.clippy.toml`, `deny.toml`, and `[workspace.lints]` / `[lints]` sections in `Cargo.toml`. These rules apply in addition to Core Rules below.

2. **Implement** — Delegate to `rust-dev:rust-coder` agent. It rediscovers guidelines, implements, then verifies its own work with `cargo clippy --workspace --tests -- -D warnings` and `cargo test --workspace` before reporting done.

3. **Review** — Invoke `rust-dev:review-rust-code` agent after rust-coder completes. This is mandatory, not optional. Convert findings into TODOs: critical/warning → fix; suggestions → triage.

4. **Fix issues one by one** — Delegate each fix to `rust-dev:rust-coder`. Do not batch unrelated fixes into one delegation.

5. **Final build** — `cargo build --workspace` (or delegate to `rust-dev:rust-builder`).

## Core Rules

1. **Edition 2024**: Always `edition = "2024"` in Cargo.toml
2. **FAIL FAST**: Every error MUST propagate with `?` or `return Err`. Logging is NOT handling. See [error-handling.md](references/error-handling.md)
3. **Dependency versions**: Use `x.x` format (e.g., `serde = "1.0"`). Find latest with `python3 scripts/check_crate_version.py `
4. **Workspace architecture**: Root Cargo.toml defines workspace only. Separate crates for lib/cli/client
5. **Error types**: `thiserror` (with backtrace) for libraries, `anyhow` for binaries/tests
6. **CLI-first config**: Never bypass CLI args. Use `from_cli_args()`, never `Default` that reads env
7. **No `env::set_var` in tests**: Pass config through function parameters
8. **Async**: Use tokio consistently
9. **Visibility**: Private (default) > `pub(crate)` > `pub`
10. **No magic numbers**: Use `const` or CLI args

## Adding Dependencies

1. Run `python3 scripts/check_crate_version.py ` to find latest version
2. Add to `[workspace.dependencies]` in root Cargo.toml with `x.x` format
3. Reference in member crates: `serde = { workspace = true }`

Common deps: `thiserror = "2.0"`, `anyhow = "1.0"`, `tokio = { version = "1", features = ["full"] }`, `serde = { version = "1.0", features = ["derive"] }`, `clap = { version = "4.5", features = ["derive"] }`

## Creating New Projects

Use the template in `assets/workspace-template/`:

```
project/
├── Cargo.toml              # Workspace root, no code
├── project/                # Library crate (thiserror)
│   ├── Cargo.toml
│   └── src/lib.rs
└── project-cli/            # Binary crate (anyhow + clap)
    ├── Cargo.toml
    └── src/main.rs
```

## Module Organization

Split modules when file exceeds ~500 lines or tests take 50%+ of file. See [module-organization.md](references/module-organization.md) for patterns.

## Error Handling

The most critical standard. See [error-handling.md](references/error-handling.md) for full rules and examples.

**Quick check:** If you see `if let Err` or `match ... Err` without `return Err` or `?`, it's a bug.

## References

- [error-handling.md](references/error-handling.md) — FAIL FAST rules, thiserror/anyhow patterns, error chain preservation
- [module-organization.md](references/module-organization.md) — When/how to split modules, test extraction
- [dependency-guide.md](references/dependency-guide.md) — Workspace deps, feature flags, common crates

## Scripts

- `scripts/check_crate_version.py` — Query crates.io for latest dependency versions

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [onsails](https://github.com/onsails)
- **Source:** [onsails/cc](https://github.com/onsails/cc)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-onsails-cc-rust-dev
- Seller: https://agentstack.voostack.com/s/onsails
- Browse the marketplace: https://agentstack.voostack.com/browse

---
Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.