Der nachfolgende Text wurden mit KI erstellt und kann Fehler enthalten. Fehler gefunden? Bei GitHub editieren
Software architecture has become increasingly vital in modern development, yet many teams struggle to communicate their architectural designs effectively. Simon Brown, creator of the C4 model and Structurizr, addresses this challenge by providing a practical framework for visualizing complex systems at different levels of abstraction.
The Evolution of Architecture Documentation
The journey toward C4 began when Brown observed a critical problem during architecture workshops: teams created completely inconsistent diagrams that neither external stakeholders nor the developers themselves could understand. While UML offered a formal approach, its complexity and the Agile movement’s informal practices left a documentation void. Brown’s solution was to formalize the ad-hoc whiteboard diagrams that actually worked, creating a simple yet structured approach that bridges this gap.
The Four Levels of C4
The C4 model comprises four hierarchical levels. The System Context diagram provides the highest-level view, showing the system as a single box with external users and dependencies. This foundational diagram is essential for understanding what’s being built and how it fits into the broader ecosystem—particularly valuable for onboarding and impact analysis when external systems change.
Container diagrams zoom into the system, revealing the individual applications and data stores that comprise it. These aren’t Docker containers but rather separately deployable units, making this level technical yet accessible to developers who need to understand deployment realities.
Component diagrams further decompose containers, showing the internal building blocks. Brown emphasizes that these should reflect actual code structure rather than aspirational designs. Interestingly, when teams develop clear heuristics for identifying components and automate diagram generation from code, they often discover their codebase becomes cleaner in the process.
The final code level shows individual classes and interfaces. Brown recommends this optional level primarily for complex components, noting that most IDEs can auto-generate such diagrams when needed.
Structurizr: From Theory to Practice
Recognizing that multiple diagrams created with separate tools inevitably diverge, Brown developed Structurizr — a modeling platform that maintains consistency across all architectural views. By defining systems once as a text-based model, teams can automatically generate synchronized diagrams in multiple formats: web-based interactive visualizations, PlantUML, Mermaid, or custom exports.
The platform’s integration of architecture decision records (ADRs), documentation, and deployment perspectives creates a comprehensive architecture documentation system — all stored as version-controllable text files.
Conclusion
The C4 model and Structurizr represent a pragmatic approach to architecture documentation. By focusing on what matters—clear communication at appropriate abstraction levels — rather than comprehensive notation, Brown has created tools that actually get used. The combination of hierarchical diagrams, decision records, and automated consistency checking provides teams with a lightweight yet powerful framework for managing architectural complexity in an increasingly distributed and cloud-native world.