On this page
Excalidraw UML & Class Diagrams for Jira lets you write UML as short text on Jira issues — class diagrams in nomnoml, sequence, state and ER diagrams in Mermaid — and annotate the model by hand on an Excalidraw whiteboard.
UML from a few lines of text
Write a class diagram in nomnoml — or a sequence, state or ER diagram in Mermaid — and it appears on the issue. Change the text to change the model; no boxes to align by hand.
Sketch around the model
Mark what changes with hand-drawn arrows and notes, paste screenshots, group parts — the whiteboard keeps the model a living sketch.
Models shared across the project
Keep the domain model, ERD and state machines on the project page, show them on every issue that touches them, and roll back to any of the last 10 versions.
Also included
- Issue panel, project page and global page — a diagram per issue, the project’s diagrams, every scene on the site.
- Built-in editors — Nomnoml, Mermaid, LaTeX Math, Graphviz, Vega-Lite, WaveDrom; the source of each stays editable.
- Shared scenes and templates — one diagram on many issues, or a new one from a copy.
- Version history — the last 10 versions; conflict-safe saving with merge.
- Over 200 shape libraries inside the app, light and dark themes, non-Latin scripts.
Runs on Atlassian
Built on Atlassian Forge: scenes are stored inside your Atlassian site, rendered in your browser, and the app makes no external calls. Anyone who can edit an issue can change its diagram. See the privacy policy.
Further reading
- nomnoml syntax: every arrow, shape and directive, tested — all 18 arrows and 25 shapes drawn by nomnoml 1.7.0, the defaults, escapes and three diagrams to copy.
Related apps
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Excalidraw UML & Class Diagrams for Confluence — the same app for Confluence.
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Excalidraw Whiteboard & Mermaid Diagrams for Jira — Mermaid first.
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Excalidraw Math Equations & LaTeX Whiteboard for Jira — LaTeX Math first.
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Excalidraw Architecture & Dependency Diagrams for Jira — Graphviz first.
Frequently asked questions
Can I edit a Nomnoml diagram after inserting it?
Yes. The Nomnoml source is stored with the diagram; choose Update, pick the diagram and change the text. The diagram keeps its place and scale in the scene.
Which diagram languages are included?
All of them in one app: Nomnoml, Mermaid, LaTeX Math, Graphviz, Vega-Lite, WaveDrom, plus Excalidraw's own hand-drawn shapes and over 200 shape libraries.
What happens if two people save the same diagram?
Nothing is overwritten. The second person's changes stay in the editor, and they can merge them with the latest version, reload it, or save theirs as a copy. The last 10 versions are kept.
Does the app send diagrams to an external server?
No. Scenes are stored in the app's Forge storage inside your Atlassian site and rendered in your browser; all renderers ship inside the app.
Can one diagram appear on several issues?
Yes. Attach a shared scene to several issues or the project page; a change shows everywhere. Or start a new diagram from a copy of a scene, which you can change freely.
Get Excalidraw UML & Class Diagrams for Jira
Free up to 10 users. Install it from the Atlassian Marketplace.