"Markup for diagram" is great so long as others have a way to edit the markup when you use the diagram in your document. Blockdiag/Seqdiag has a pretty good RS

"Markup for diagram" is great so long as others have a way to edit the markup when you use the diagram in your document. Blockdiag/Seqdiag has a pretty good RST integration for Sphinx. Lately I've been using the ZenUML diagram plugin for Confluence which lets you do sequence and other diagrams using Mermaid-JS. Considering that the author of swimlanes.io seems to have mastered the part where the diagram is encoded into a URL, it feels like making plugins to popular documentation systems is the obvious next step to making this useful for engineering orgs.