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skills/architecture-patterns/SKILL.md

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+---
+name: architecture-patterns
+description: Implement proven backend architecture patterns including Clean Architecture, Hexagonal Architecture, and Domain-Driven Design. Use when architecting complex backend systems or refactoring existing applications for better maintainability.
+---
+
+# Architecture Patterns
+
+Master proven backend architecture patterns including Clean Architecture, Hexagonal Architecture, and Domain-Driven Design to build maintainable, testable, and scalable systems.
+
+## Use this skill when
+
+- Designing new backend systems from scratch
+- Refactoring monolithic applications for better maintainability
+- Establishing architecture standards for your team
+- Migrating from tightly coupled to loosely coupled architectures
+- Implementing domain-driven design principles
+- Creating testable and mockable codebases
+- Planning microservices decomposition
+
+## Do not use this skill when
+
+- You only need small, localized refactors
+- The system is primarily frontend with no backend architecture changes
+- You need implementation details without architectural design
+
+## Instructions
+
+1. Clarify domain boundaries, constraints, and scalability targets.
+2. Select an architecture pattern that fits the domain complexity.
+3. Define module boundaries, interfaces, and dependency rules.
+4. Provide migration steps and validation checks.
+
+Refer to `resources/implementation-playbook.md` for detailed patterns, checklists, and templates.
+
+## Resources
+
+- `resources/implementation-playbook.md` for detailed patterns, checklists, and templates.