Mermaid Flow

A visual, drag-and-drop editor for Mermaid flowcharts inside Obsidian.

Build and rearrange diagrams by moving nodes and drawing connections — Mermaid Flow writes the underlying mermaid code for you, so no syntax knowledge is required.

Your edits round-trip safely: Mermaid Flow reads your existing Mermaid blocks, lets you edit them visually, and writes them back — without losing custom syntax.

✨ Features

• Drag-and-drop canvas — move nodes, draw connections, resize, and multi-select on an SVG editing surface.
• No syntax required — the plugin generates and updates the Mermaid code as you work.
• Shapes & subgraphs — multiple node shapes, plus grouping of nodes into subgraphs.
• Themes & direction — switch diagram theme and flow direction (Top-Bottom, Left-Right, and more).
• Auto-layout & lock — apply layout presets or arrange nodes automatically, then lock the layout.
• AI assist (optional) — generate a flowchart from a text prompt using your own provider (OpenAI, Gemini, Anthropic, or a local CLI).
• Raw code view — open the live Mermaid source side-by-side and edit it directly; changes sync both ways.
• Undo / redo, zoom & export — full history, canvas zoom, and diagram export from the toolbar.
• Persistent layouts — manual node positions are saved in hidden Mermaid comments, so your arrangement survives reloads (and the diagram still renders normally).
• Works everywhere — edit from Reading mode, Live Preview, or Source mode.

🎬 See it in action

Edit an existing diagram

Click Edit on any rendered Mermaid block and rearrange it visually — your advanced syntax is preserved on save.

Generate with AI

Describe what you want and let your configured AI provider draft the flowchart, then refine it on the canvas.

🚀 Getting started

Install

1. Open Settings → Community plugins and browse for Mermaid Flow.
2. Click Install, then Enable.

Usage

Create a diagram

• Click the ribbon icon (workflow), or run Mermaid Flow: Insert visual Mermaid diagram.

Edit an existing diagram

• Click the Edit button on any rendered Mermaid block (Reading mode / Live Preview), or
• Place your cursor inside a mermaid code block and run Mermaid Flow: Edit Mermaid diagram visually.

Save your changes

• Use Save to write the diagram back to your note, or Discard to close without saving.
• In the embedded pane, enable Auto-save to persist changes automatically as you edit.

🔒 Advanced syntax & safety

The editor focuses on flowchart structure. Advanced or unrecognized Mermaid syntax in an existing diagram (for example click, classDef, or linkStyle directives) is preserved verbatim when you edit and re-save, and is rendered by Obsidian's own Mermaid engine — Mermaid Flow never executes diagram code itself.

🗺️ Roadmap

Done

• Visual flowchart editor (drag, connect, subgraphs, undo/redo, zoom/pan)
• Safe round-trip (advanced Mermaid lines preserved)
• Custom node/edge styling + themes + classDefs
• Component library (save / insert snippets)
• AI generate & improve (HTTP + desktop CLI)
• Sequence, mindmap, and ER visual editors (MVP)

Next

• Richer sequence fragments (loops, alts, activations)
• Stronger mindmap / ER canvas (drag layout, fuller editing)
• Additional Mermaid diagram kinds beyond code-view fallback

🤝 Contributing

Contributions are welcome! See the Contribution Guide and Architecture Overview to get started.

📄 License

Licensed under the GNU General Public License v3.0.