/m11-ecosystem

name: m11-ecosystem
description: "Use when integrating crates or ecosystem questions. Keywords: E0425, E0433, E0603, crate, cargo, dependency, feature flag, workspace, which crate to use, using external C libraries, creating Python extensions, PyO3, wasm, WebAssembly, bindgen, cbindgen, napi-rs, cannot find, private, crate recommendation, best crate for, Cargo.toml, features, crate 推荐, 依赖管理, 特性标志, 工作空间, Python 绑定"
user-invocable: false

Current Dependencies (Auto-Injected)

!`grep -A 100 '^\[dependencies\]' Cargo.toml 2>/dev/null | head -30 || echo "No Cargo.toml found"`

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Ecosystem Integration

> **Layer 2: Design Choices**

Core Question

**What's the right crate for this job, and how should it integrate?**

Before adding dependencies:

• Is there a standard solution?
• What's the maintenance status?
• What's the API stability?

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Integration Decision → Implementation

| Need | Choice | Crates | |------|--------|--------| | Serialization | Derive-based | serde, serde_json | | Async runtime | tokio or async-std | tokio (most popular) | | HTTP client | Ergonomic | reqwest | | HTTP server | Modern | axum, actix-web | | Database | SQL or ORM | sqlx, diesel | | CLI parsing | Derive-based | clap | | Error handling | App vs lib | anyhow, thiserror | | Logging | Facade | tracing, log |

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Thinking Prompt

Before adding a dependency:

1. **Is it well-maintained?**

• Recent commits?
• Active issue response?
• Breaking changes frequency?

2. **What's the scope?**

• Do you need the full crate or just a feature?
• Can feature flags reduce bloat?

3. **How does it integrate?**

• Trait-based or concrete types?
• Sync or async?
• What bounds does it require?

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Trace Up ↑

To domain constraints (Layer 3):

"Which HTTP framework should I use?"
    ↑ Ask: What are the performance requirements?
    ↑ Check: domain-web (latency, throughput needs)
    ↑ Check: Team expertise (familiarity with framework)

| Question | Trace To | Ask | |----------|----------|-----| | Framework choice | domain-* | What constraints matter? | | Library vs build | domain-* | What's the deployment model? | | API design | domain-* | Who are the consumers? |

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Trace Down ↓

To implementation (Layer 1):

"Integrate external crate"
    ↓ m04-zero-cost: Trait bounds and generics
    ↓ m06-error-handling: Error type compatibility

"FFI integration"
    ↓ unsafe-checker: Safety requirements
    ↓ m12-lifecycle: Resource cleanup

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Quick Reference

Language Interop

| Integration | Crate/Tool | Use Case | |-------------|------------|----------| | C/C++ → Rust | `bindgen` | Auto-generate bindings | | Rust → C | `cbindgen` | Export C headers | | Python ↔ Rust | `pyo3` | Python extensions | | Node.js ↔ Rust | `napi-rs` | Node addons | | WebAssembly | `wasm-bindgen` | Browser/WASI |

Cargo Features

| Feature | Purpose | |---------|---------| | `[features]` | Optional functionality | | `default = [...]` | Default features | | `feature = "serde"` | Conditional deps | | `[workspace]` | Multi-crate projects |

Error Code Reference

| Error | Cause | Fix | |-------|-------|-----| | E0433 | Can't find crate | Add to Cargo.toml | | E0603 | Private item | Check crate docs | | Feature not enabled | Optional feature | Enable in `features` | | Version conflict | Incompatible deps | `cargo update` or pin | | Duplicate types | Different crate versions | Unify in workspace |

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Crate Selection Criteria

| Criterion | Good Sign | Warning Sign | |-----------|-----------|--------------| | Maintenance | Recent commits | Years inactive | | Community | Active issues/PRs | No response | | Documentation | Examples, API docs | Minimal docs | | Stability | Semantic versioning | Frequent breaking | | Dependencies | Minimal, well-known | Heavy, obscure |

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Anti-Patterns

| Anti-Pattern | Why Bad | Better | |--------------|---------|--------| | `extern crate` | Outdated (2018+) | Just `use` | | `#[macro_use]` | Global pollution | Explicit import | | Wildcard deps `*` | Unpredictable | Specific versions | | Too many deps | Supply chain risk | Evaluate necessity | | Vendoring everything | Maintenance burden | Trust crates.io |

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Related Skills

| When | See | |------|-----| | Error type design | m06-error-handling | | Trait integration | m04-zero-cost | | FFI safety | unsafe-checker | | Resource management | m12-lifecycle |