Architecture documentation
C4 model
Hierarchical approach to architecture diagrams with four levels of detail:
Zooming in with the C4 model
Customer[Person]
Contoso Ordering[Software system]
ERP[External system]
Email[External system]
System in context with users and external dependencies. Shows what the system does and who uses it. Non-technical stakeholders can understand this view.
Architecture decision records (ADRs)
Document significant architecture decisions with context, decision, and consequences:
# ADR 001: Use Azure Cosmos DB for the product catalog **Status:** Accepted **Date:** 2024-01-15 **Deciders:** Architecture team ## Context The product catalog needs a globally distributed, low-latency data store. Read volume will be high; eventual consistency is acceptable. ## Decision Use Azure Cosmos DB with multi-region writes. ## Consequences + Global distribution with single-digit-millisecond reads + Autoscale to absorb traffic spikes + Several consistency levels to choose from - Higher cost than Azure SQL Database - The team needs to learn Cosmos DB query patterns
Architecture governance
Architecture review board
Establish governance for architecture decisions:
- Regular reviews: Quarterly architecture reviews for major initiatives
- Peer review: Architecture designs reviewed by senior engineers
- Standards enforcement: Automated checks for security, compliance, naming conventions
- Technology radar: Track approved, trial, and deprecated technologies
- Reference implementations: Sample projects demonstrating patterns
Technical debt management
- Debt register: Catalog known technical debt with priority and effort estimates
- Allocation: Dedicate 20% of sprint capacity to debt reduction
- Metrics: Track code coverage, cyclomatic complexity, dependency health
- Refactoring: Continuous incremental improvements vs. big rewrites