playbook/outfitter-agents/plugins/outfitter/skills/architecture/references/rust-architecture.md

Rust Architecture

When to Choose Rust

Strong fit:

• Performance-critical services (compute-heavy, low-latency)
• Resource-constrained environments
• Systems programming needs
• Memory safety critical (no GC pauses)
• Concurrent processing with correctness guarantees

May not be worth it:

• Prototype/MVP stage (slower iteration)
• Small team without Rust experience
• Standard CRUD API (TS faster to develop)
• Heavy dependency on ecosystem libraries only in other languages

Stack Recommendations

Web services

Component	Recommendation
Runtime	tokio (async runtime, de facto standard)
Web framework	axum (modern, type-safe) or actix-web (mature, fast)
Database	sqlx (compile-time checked), diesel (full ORM)
Serialization	serde + serde_json, bincode for binary
Observability	tracing + tracing-subscriber
Errors	thiserror (libraries), anyhow (applications)

Project structure

my-service/
├── Cargo.toml          # Workspace manifest
├── crates/
│   ├── api/            # HTTP handlers, routing
│   ├── domain/         # Business logic, pure Rust
│   ├── persistence/    # Database access
│   └── common/         # Shared utilities

Operational considerations

• Build times longer than TS (use sccache, mold linker)
• Binary size larger (use cargo-bloat to analyze)
• Memory usage lower at runtime
• Deploy as single static binary (easy containerization)
• Cross-compilation more complex

Tradeoffs vs TypeScript

Aspect	Rust	TypeScript
Memory	5-10x lower	Higher
Execution	2-10x faster	Slower
Bug detection	Compile-time (null, races)	Runtime possible
GC pauses	None	Yes
Development speed	Slower (borrow checker)	Faster iteration
Ecosystem	Smaller for web	Massive (npm)
Hiring	Harder	Easy