github.com• Aug 17, 2026• 1 min read
Show HN: Visimer – open-source visual editor for Mermaid diagramsHi HN, Nick here, founder at OpenKnowledge. We built an open source library, Visimer, for editing Mermaid diagrams with a what-you-see-is-what-you-get visual editor. Try the playground at https://visimer.com/playground. You can rename labels, change shapes, add new nodes, etc. by clicking and dragging the visual canvas.We set out to build this originally for OpenKnowledge, our markdown wysiwyg editor, then realized it’d be great to share it as a proper embeddable component library so that other apps can leverage it as well.Our general take is that AI is great for generating content, but whenever you want to tweak fine details, for example to create an artifact sharable with others, point-edit functionality is much better. We built Visimer to bring that to Mermaid diagrams, just like we did for markdown.Some technical bits:- Leverages the native Mermaid.js renderer for visualizing the Mermaid diagram true to how it’s intended. We add point-edit functionality on top.- We tried re-generat