PlantUML definitions are available via the Structurizr CLI export command, using the -format plantuml parameter.

@startuml(id=SystemContext)
title Software System - System Context
caption An example of a System Context diagram.

skinparam {
  shadowing false
  arrowFontSize 10
  defaultTextAlignment center
  wrapWidth 200
  maxMessageSize 100
}
hide stereotype
top to bottom direction
skinparam rectangle<<1>> {
  BackgroundColor #08427b
  FontColor #ffffff
  BorderColor #052E56
}
skinparam rectangle<<2>> {
  BackgroundColor #1168bd
  FontColor #ffffff
  BorderColor #0B4884
}
rectangle "==User\n<size:10>[Person]</size>\n\nA user of my software system." <<1>> as 1
rectangle "==Software System\n<size:10>[Software System]</size>\n\nMy software system." <<2>> as 2
1 .[#707070].> 2 : "Uses"
@enduml

C4-PlantUML definitions are available via the Structurizr CLI export command, using the -format plantuml/c4plantuml parameter.

@startuml(id=SystemContext)
!includeurl https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4.puml
!includeurl https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Context.puml
!includeurl https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Container.puml
!includeurl https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Component.puml
LAYOUT_WITH_LEGEND()

title Software System - System Context
caption An example of a System Context diagram.

Person(1, "User", "A user of my software system.")
System(2, "Software System", "My software system.")
Rel_D(1, 2, "Uses", "")
@enduml

Mermaid definitions are available via the Structurizr CLI export command, using the -format mermaid parameter.

graph TB
  linkStyle default fill:#ffffff
  1["<div style='font-weight: bold'>User</div><div style='font-size: 70%; margin-top: 0px'>[Person]</div><div style='font-size: 80%; margin-top:10px'>A user of my software system.</div>"]
  style 1 fill:#08427b,stroke:#052e56,color:#ffffff
  2["<div style='font-weight: bold'>Software System</div><div style='font-size: 70%; margin-top: 0px'>[Software System]</div><div style='font-size: 80%; margin-top:10px'>My software system.</div>"]
  style 2 fill:#1168bd,stroke:#0b4884,color:#ffffff
  1-. "<div>Uses</div><div style='font-size: 70%'></div>" .->2

WebSequenceDiagram definitions are available via the Structurizr CLI export command, using the -format websequencediagrams parameter. Only dynamic views are supported.

Ilograph definitions are available via the Structurizr CLI export command, using the -format ilograph parameter. A single Ilograph export contains the model and all views.

resources:
  - id: "1"
    name: "User"
    subtitle: "[Person]"
    description: "A user of my software system."
    backgroundColor: "#08427b"
    color: "#ffffff"


  - id: "2"
    name: "Software System"
    subtitle: "[Software System]"
    description: "My software system."
    backgroundColor: "#1168bd"
    color: "#ffffff"


perspectives:
  - name: Static Structure
    relations:
      - from: "1"
        to: "2"
        label: "Uses"

The Structurizr DSL (as mentioned on the ThoughtWorks Tech Radar - Techniques - Diagrams as code) allows you to create multiple diagrams based upon the C4 model, in multiple output formats, from a single DSL source file.