PlantUML
SlapOS instance for a self hosted version of http://www.plantuml.com/
README for this slapos software:
PlantUML
PlantUML is a service rendering UML diagrams defined in a simple and intuitive language.
Each diagram has a unique URL which is made of an encoded version of the diagram code.
Diagrams can be rendered as png, svg or ascii art text.
See http://plantuml.com/PlantUML_Language_Reference_Guide.pdf for a full reference on the diagram language.