solid-go

SOLID Go - 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 Go docs via Context7
3. fuse-ai-pilot:sniper - Post-implementation validation

DRY - Reuse Before Creating (MANDATORY)

Before writing ANY new code:

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

Architecture (Modules MANDATORY)

| Layer | Location | Max Lines | |-------|----------|-----------| | Handlers | internal/modules/[feature]/handlers/ | 50 | | Services | internal/modules/[feature]/services/ | 100 | | Repositories | internal/modules/[feature]/repositories/ | 100 | | Ports (interfaces) | internal/modules/[feature]/ports/ | 30 | | Models | internal/modules/[feature]/models/ | 50 | | Shared | internal/core/{services,ports,models}/ | - |

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

Critical Rules (MANDATORY)

| Rule | Value | |------|-------| | File limit | 100 lines (split at 90) | | Handlers | < 50 lines, delegate to services | | Interfaces | ports/ directory ONLY | | Godoc | Every exported function documented | | Accept interfaces | Return structs | | Small interfaces | 1-3 methods max (Go idiom) |

Reference Guide

Concepts

| Topic | Reference | When to consult | |-------|-----------|-----------------| | SOLID Overview | [solid-principles.md](references/solid-principles.md) | Quick reference | | SRP | [single-responsibility.md](references/single-responsibility.md) | Fat structs | | OCP | [open-closed.md](references/open-closed.md) | Adding providers | | LSP | [liskov-substitution.md](references/liskov-substitution.md) | Contracts | | ISP | [interface-segregation.md](references/interface-segregation.md) | Fat interfaces | | DIP | [dependency-inversion.md](references/dependency-inversion.md) | Injection | | Architecture | [architecture-patterns.md](references/architecture-patterns.md) | Hex/modular |

Templates

| Template | When to use | |----------|-------------| | [module.md](references/templates/module.md) | Feature module structure | | [service.md](references/templates/service.md) | Business logic service | | [interface.md](references/templates/interface.md) | Port definition | | [handler.md](references/templates/handler.md) | HTTP handler | | [error.md](references/templates/error.md) | Custom errors | | [test.md](references/templates/test.md) | Table-driven tests |

Forbidden

| Anti-Pattern | Fix | |--------------|-----| | Files > 100 lines | Split at 90 | | Interfaces in impl files | Move to ports/ directory | | Fat interfaces (4+ methods) | Split into small interfaces | | Flat internal/ structure | Use internal/modules/[feature]/ | | init() for dependency wiring | Use constructor injection |