| name | architecture |
| description | Design scalable system architectures using DDD, Clean Architecture, cloud-native patterns |
| allowed-tools | ["Read","Glob","Grep","WebSearch"] |
| context | fork |
| user-invocable | true |
| version | 2.0.0 |
Architecture Design Skill
Reusable workflow extracted from baccio-tech-architect expertise.
Design scalable, maintainable, secure system architectures using DDD, Clean Architecture, cloud-native patterns.
When to Use
New system design | Legacy modernization | Stack selection | Scalability planning | Microservices design | Cloud migration | Debt evaluation | Architecture review
Workflow
| Step | Actions |
|---|
| 1. Requirements | Gather functional/NFRs, constraints (budget, timeline, team), scale (users, data, traffic), compliance |
| 2. Domain Model | Apply DDD: bounded contexts, aggregates, entities, ubiquitous language |
| 3. Pattern Selection | Choose style (monolith/microservices/serverless), patterns (CQRS, Event Sourcing, Saga), Clean Architecture |
| 4. Tech Stack | Evaluate options vs requirements, team expertise, vendor lock-in, cost, compliance |
| 5. Scalability | Horizontal/vertical scaling, caching (app/CDN/DB), load balancing, sharding, geo-distribution |
| 6. Security | Zero-Trust, auth/authz, encryption (at-rest/in-transit), boundaries, defense-in-depth |
| 7. Observability | Structured logging, metrics (Prometheus, CloudWatch), tracing, dashboards, alerts |
| 8. Documentation | ADRs, C4 diagrams, API contracts/versioning, deployment architecture, capacity planning |
Inputs
- Business requirements (problem to solve)
- NFRs (performance, security, compliance)
- Scale (current/projected users, data, traffic)
- Constraints (budget, timeline, team skills, existing systems)
- Compliance (GDPR, HIPAA, SOC2, etc.)
Outputs
- Architecture Blueprint
- ADRs (decision records with rationale)
- Tech Stack Recommendation
- Scalability Plan
- Security Architecture
- Deployment Diagrams
- Migration Roadmap
Architecture Patterns
Styles
| Pattern | Traits |
|---|
| Monolithic | Single deployable, simpler, less scalable |
| Microservices | Independent services, complex, highly scalable |
| Serverless | Event-driven, pay-per-use, elastic |
| Modular Monolith | Compromise between monolith and microservices |
| SOA | Enterprise service bus |
Design Patterns
| Pattern | Use Case |
|---|
| DDD | Bounded contexts, aggregates, entities |
| Clean Architecture | Dependency inversion, layers, boundaries |
| CQRS | Command Query Responsibility Segregation |
| Event Sourcing | Event log as source of truth |
| Saga | Distributed transactions |
| API Gateway | Single entry point |
| BFF | Backend for Frontend (API per client) |
Communication
- Sync: REST, GraphQL, gRPC
- Async: Kafka, RabbitMQ, SQS
- Pub/Sub: Event-driven
- RPC: Request-Reply
ADR Template
## Decision: [Technology/Pattern]
### Context
[Problem, constraints]
### Options
1. **Option A**: [Pros/Cons/Cost]
2. **Option B**: [Pros/Cons/Cost]
### Decision
[Choice with rationale]
### Consequences
- Positive: [Benefits]
- Negative: [Drawbacks]
- Mitigation: [Actions]
NFR Checklist
See nfr-checklist.md for performance, availability, security, observability, maintainability requirements.
Example
Input: E-commerce platform, 10K users, 99.9% uptime, PCI DSS
Steps:
1. Requirements: User accounts, catalog, cart, checkout
2. Domain: User, Product, Cart, Order contexts
3. Pattern: Microservices + API Gateway + Event-driven
4. Stack: Node.js, PostgreSQL, Redis, Kafka, AWS ECS/RDS
5. Scale: Horizontal (ECS), read replicas, CDN
6. Security: OAuth2+JWT, PCI gateway, encryption
7. Observability: CloudWatch, X-Ray, Grafana
8. Docs: ADRs, C4 diagrams, API specs
Output: Blueprint + ADRs + diagrams
Tech Stack Evaluation
| Criterion | Weight | Option A | Option B | Option C |
|---|
| Team expertise | 20% | 8/10 | 5/10 | 6/10 |
| Scalability | 25% | 9/10 | 7/10 | 8/10 |
| Cost | 15% | 6/10 | 9/10 | 7/10 |
| Community | 10% | 9/10 | 8/10 | 6/10 |
| Compliance | 15% | 8/10 | 7/10 | 9/10 |
| Lock-in | 15% | 7/10 | 5/10 | 8/10 |
| Total | 100% | 7.9 | 6.9 | 7.5 |
Related Agents
- baccio-tech-architect - Full reasoning/decision-making
- luca-security-expert - Security validation
- dan-engineering-gm - Leadership alignment
- marco-devops-engineer - Infrastructure/deployment
- domik-mckinsey-strategic-decision-maker - Strategic decisions
Engineering Fundamentals
- Document ADRs for all major decisions
- Apply proven design patterns
- Trade studies before decisions
- Technical spikes for high-risk unknowns
- Design for NFRs from day one
- Infrastructure as Code
- GitOps workflows
