mermaid-render

Render beautiful Mermaid diagrams to PNG from the command line.

A native Rust CLI tool with modern styling using the Flat UI color palette.

Installation

npm install -g mermaid-render

Usage

# Basic usage
mermaid-render -i diagram.mmd -o output.png

# With dark theme
mermaid-render -i diagram.mmd -o output.png --theme dark

# With 2x scale (for retina displays)
mermaid-render -i diagram.mmd -o output.png --scale 2

# Show help
mermaid-render --help

Supported Diagram Types

Flowcharts

graph TD
    A[Start] --> B{Decision}
    B -->|Yes| C[Action]
    B -->|No| D[End]

Supported node shapes:

• [text] - Rectangle
• (text) - Rounded rectangle
• {text} - Diamond
• ((text)) - Circle
• ([text]) - Stadium
• [(text)] - Cylinder

Directions: TD, TB, BT, LR, RL

Sequence Diagrams

sequenceDiagram
    Alice->>Bob: Hello
    Bob-->>Alice: Hi there

Themes

• default - Light theme with Flat UI colors
• dark - Dark theme for dark backgrounds

Features

• Native Rust performance (no browser/Node.js runtime needed)
• Beautiful modern styling with rounded corners and shadows
• Anti-aliased rendering
• Embedded Open Sans font
• Support for flowcharts and sequence diagrams

License

MIT