Suggestion: Reference C4 Model as an Diagramming Approach in arc42

[sziniuk-at-bentley]

Suggestion: Reference C4 Model as an Optional Diagramming Approach in arc42

Description

Please consider adding a short reference in arc42 documentation to the C4 model as an optional way to implement diagrams. This is not to make C4 mandatory, but to acknowledge it as a widely used and compatible approach.

Why

• Many teams already use C4 for architecture diagrams.
• Mapping C4 to arc42 views helps reuse existing practices and maintain consistency.
• C4 integrates well with diagrams-as-code tools (e.g., Structurizr, PlantUML), which supports automation, version control, and CI/CD workflows—important for modern architecture documentation.

Proposed Mapping

arc42 View	Closest C4 Level	Notes
Context	Context	Direct match
System Whitebox (Logical)	Container	arc42 prefers logical-only; C4 includes tech
Building Block Breakdown	Component	Same choice: logical-only or tech-inclusive
Runtime view (flow, sequence)	Dynamic	Direct match
Deployment	Deployment	Direct match

Clarification

arc42 separates logical and technical concerns:

• Logical views (System Whitebox, deeper levels) → ideally no technology details.
• Deployment view → technology expected.

If C4 diagrams are used:

• Should tech annotations be omitted in logical views to stay aligned with arc42?
• Or is tech-inclusive acceptable as an alternative?

Proposal

• Add a section like “Possible diagramming approaches” mentioning C4.
• Provide guidance on adapting C4 diagrams to arc42 principles (logical-only vs tech-inclusive).
• Optionally include examples and diagrams-as-code recommendations.

Would the community be open to this addition?
I can draft a mapping guide and examples if this idea is accepted.

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References

• C4 Model Official Site

[mverburg]

This seems like a very reasonable request. Simon Brown also references arc42 in the faq of the C4 model pages.

https://c4model.com/faq#can-we-combine-c4-and-arc42