thurbeen/m11-ecosystem

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 |