crystal-facet-uml is a desktop UML and SysML modeling application designed to document system and software architecture from multiple viewpoints.
It helps architects build a consistent set of diagrams by keeping element names, hierarchies, relationships, and shared model data aligned across the project, while storing that data in a JSON-based format that can be versioned alongside source code.
This is free and open source software.
Key Features
- Creates, modifies, and deletes UML and SysML diagrams, elements, and relationships.
- Maintains a shared meta-model so elements and relationships stay consistent across multiple diagrams.
- Supports part-automatic layout, with user control over messages and transitions in sequence and timing diagrams.
- Exports diagrams and models to SVG, PDF, PS, PNG, HTML, DocBook, JSON, and XMI formats.
- Offers both a graphical interface and command line operation for batch export, JSON import, and checking or repairing model files.
Website: github.com/awarnke/crystal-facet-uml
Support:
Developer: Andreas Warnke
License: Apache License 2.0

crystal-facet-uml is written in C. Learn C with our recommended free books and free tutorials.
Related Software
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|---|---|
| Eclipse Papyrus | Edit models based on UML and related languages |
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| Mermaid | Generate diagrams from markdown-like text |
| Umple | Create UML models textually |
| Modelio | UML and BPMN modeling environment |
| Gaphor | Simple UML and SysML modeling tool |
| Umbrello | UML Modeller based on KDE technology |
| UMLet | Java-based UML tool |
| JetUML | Sketch software design ideas with a minimum of fuss |
| Violet | Designed for people who need to produce simple UML diagrams |
| Dia | GTK+ based diagram creation software |
| ArgoUML | UML modeling tool |
| crystal-facet-uml | Desktop UML and SysML modeling application |
| UML Designer | UML tool based on Sirius and Eclipse |
Read our verdict in the software roundup.
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