fusengine/solid-rust

SOLID Rust - Modular Architecture

Agent Workflow (MANDATORY)

Before ANY implementation, use TeamCreate to spawn 3 agents:

1. fuse-ai-pilot:explore-codebase - Analyze existing architecture
2. fuse-ai-pilot:research-expert - Verify Rust docs via Context7
3. fuse-ai-pilot:sniper - Post-implementation validation

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DRY - Reuse Before Creating (MANDATORY)

Before writing ANY new code:

1. Grep the codebase for similar traits, services, or logic
2. Check shared locations: src/core/services/, src/core/traits/
3. If similar code exists -> extend/reuse instead of duplicate
4. If code will be used by 2+ features -> create it in src/core/

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Architecture (Modules MANDATORY)

| Layer | Location | Max Lines | |-------|----------|-----------| | Handlers | src/modules/[feature]/handlers.rs | 50 | | Services | src/modules/[feature]/services.rs | 100 | | Repositories | src/modules/[feature]/repository.rs | 100 | | Traits | src/modules/[feature]/traits.rs | 30 | | Models | src/modules/[feature]/models.rs | 50 | | Shared | src/core/{services,traits,models}/ | - |

NEVER use flat src/ structure - always src/modules/[feature]/

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Critical Rules (MANDATORY)

| Rule | Value | |------|-------| | File limit | 100 lines (split at 90) | | Handlers | < 50 lines, delegate to services | | Traits | traits.rs or src/core/traits/ ONLY | | Rustdoc | /// on every public item | | Error handling | Use thiserror for custom errors | | Generics | Use trait bounds, not concrete types |

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Reference Guide

Concepts

| Topic | Reference | When to consult | |-------|-----------|-----------------| | SOLID Overview | solid-principles.md | Quick reference | | SRP | single-responsibility.md | Fat structs | | OCP | open-closed.md | Adding impls | | LSP | liskov-substitution.md | Trait contracts | | ISP | interface-segregation.md | Fat traits | | DIP | dependency-inversion.md | Generics/DI | | Architecture | architecture-patterns.md | Modular crate |

Templates

| Template | When to use | |----------|-------------| | module.md | Feature module structure | | service.md | Business logic service | | trait-def.md | Trait definition | | handler.md | HTTP handler (Axum) | | error.md | Custom errors (thiserror) | | test.md | Unit + integration tests |

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Forbidden

| Anti-Pattern | Fix | |--------------|-----| | Files > 100 lines | Split at 90 | | Traits in impl files | Move to traits.rs | | Box<dyn Any> | Use proper trait bounds | | Flat src/ structure | Use src/modules/[feature]/ | | Unwrap in library code | Use Result<T, E> |