MermaidJS Editor is a project I vibe-coded on a trip to a café and was also done in around a couple of hours or so.

GitHub - jerieljan/mermaidjs-editor: A basic MermaidJS editor.

My primary motivation was originally to try out Claude Code, but it turns out that I needed a speedy, no-nonsense Mermaid editor anyway that I can easily export and screenshot for other uses.

(Read more of this in this page: June 14, 2025 - Lessons Learned on “Vibe Coding” a MermaidJS Editor)