Context Diagram

The one to draw first, and often the only one a stakeholder needs.

• Format.puml
• Length13 lines
• LibraryC4-PlantUML

The source

13 lines of PlantUML, and pulls in C4-PlantUML. Copy it, or open the template inside Gnomon and render it as it is.

@startuml
!include https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Context.puml

title System Context Diagram

Person(user, "User", "A user of the system")
System(system, "System", "The system being designed")
System_Ext(external, "External System", "An external dependency")

Rel(user, system, "Uses")
Rel(system, external, "Calls")

@enduml

Others in C4 model diagrams

• Container DiagramIndependently deployable or runnable things: a service, a database, a SPA. Not classes.
• Component DiagramInside one container. Draw this only when a container is big enough to need it.
• Dynamic DiagramFor a specific flow through the static structure: numbered steps, one scenario.
• Deployment DiagramMaps containers onto infrastructure. Where a container diagram cannot answer "where does this run?".