Mermaid ZenUML Diagram Cheat Sheet

A sequence diagram, written for a method call.

Every picture on this page was drawn byMernyx, the native Mermaid editor for macOS. Not by a browser running Mermaid.js — the same renderer the app uses for its canvas.

The messages

A single arrow is a call, and a double arrow is a reply.

zenuml
    Alice->John: Hello
    John-->Alice: Hi
    Alice->Alice: think

A ZenUML diagram with two lifelines, Alice and John, exchanging a Hello and a Hi, and a third message from Alice to herself labelled think.

Setting the order

Name the participants on their own lines to order them yourself, instead of the order they first appear in.

zenuml
    Alice->John: Hello
    John-->Alice: Hi
    John->John: think
    Alice->John: Hello
    John-->Alice: Hi

A ZenUML diagram with two lifelines, Bob and Alice, and a message from Alice to Bob saying Hi Bob.

Draw it in Mernyx.

Open a .mmd file, move a node on the canvas, and the source comes with it. Native on macOS, no browser involved.

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