Coool
https://github.com/mermaid-js/mermaid#readme
https://mermaid-js.github.io/mermaid/#/flowchart

  graph TD;
      A-->B;
      A-->C;
      B-->D;
      C-->D;

sequenceDiagram
Alice->>John: Hello John, how are you?
loop Healthcheck
    John->>John: Fight against hypochondria
end
Note right of John: Rational thoughts!
John-->>Alice: Great!
John->>Bob: How about you?
Bob-->>John: Jolly good!

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