http://plantuml.com https://plugins.jetbrains.com/plugin/7017-plantuml-integration/ https://plugins.jetbrains.com/plugin/10387-sketch-it- https://bitbucket.org/pmesmeur/sketch.it/src/develop/ https://mermaidjs.github.io
ref - https://news.ycombinator.com/item?id=21564990
origin - https://www.pipiscrew.com/?p=15804 ask-hn-a-modern-looking-uml-diagram-tool