Online sequence diagrams from code. Used to be good but now lacks functionality and design. Has interactive diagrams which is cool.
Appian - See how Appian, leading provider of modern low-code and BPM software solutions, has helped transform the businesses of over 3.5 million users worldwide.
draw.io - Online diagramming application
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SequenceDiagram.org - Clean and fast online sequence diagram tool using scripting and Drag and Drop
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