A .NET library for rendering Mermaid diagrams to SVG. No browser or JavaScript runtime required.

This project participates in the Open Source Maintenance Fee. The source code is freely available under the terms of the license. To support sustainable maintenance, use of the project's official binary releases in revenue-generating activities and all government agencies requires adherence to the Open Source Maintenance Fee EULA. The fee is paid by sponsoring Papyrine.

This project uses SponsorCheck to surface a build-time reminder in consuming projects that are not yet sponsoring.

https://nuget.org/packages/Naiad/

var svg = Mermaid.Render(
    """
    flowchart LR
        A[Start] --> B[Process] --> C[End]
    """);

The diagram type is automatically detected from the input.

var svg = Mermaid.Render(
    input,
    new RenderOptions
    {
        Padding = 20,
        FontSize = 14,
        FontFamily = "Arial, sans-serif"
    });

Naiad can render icons from iconify icon packs. Packs are not bundled — load the ones you need (in the iconify JSON format) from a file or a stream:

IconPack.Load("logos.json");

// ...or from a stream
using var stream = File.OpenRead("logos.json");
IconPack.Load(stream);

Pack files are published as @iconify-json/* packages (the icons.json file), e.g. @iconify-json/logos. Load registers the pack under its prefix and returns it. Register all packs once at startup — calling IconPack.Load after the first Mermaid.Render throws a MermaidException.

Once loaded, reference icons as prefix:name wherever a diagram supports icons — architecture services and groups, flowchart node labels, and mindmap nodes:

// Architecture
Mermaid.Render(
    """
    architecture-beta
    service fn(logos:aws-lambda)[Lambda]
    service db(logos:postgresql)[Database]
    fn:R -- L:db
    """);

// Flowchart (inline in labels)
Mermaid.Render(
    """
    flowchart LR
        A[logos:redis Cache] --> B[logos:postgresql DB]
    """);

// Mindmap
Mermaid.Render(
    """
    mindmap
      Project
        Storage ::icon(logos:aws-s3)
    """);

Single-color icons (e.g. mdi, tabler) inherit the surrounding color; multi-color icons (e.g. logos) keep their own palette.

FontAwesome icons also work in flowcharts (fa:fa-name) and mindmaps (::icon(fa fa-name)) without loading a pack.

• Flowchart / Graph
• Sequence Diagram
• Class Diagram
• State Diagram
• Entity Relationship Diagram
• Gantt Chart
• Pie Chart
• Git Graph
• Mindmap
• Timeline
• User Journey
• Quadrant Chart
• Requirement Diagram
• C4 Diagrams (Context, Container, Component, Deployment)
• Kanban
• XY Chart (beta)
• Sankey (beta)
• Block Diagram (beta)
• Packet Diagram (beta)
• Architecture (beta)
• Radar (beta)
• Treemap (beta)

Auto-generated documentation from the test suite.

• C4
• Class
• EntityRelationship
• Flowchart
• Gantt
• GitGraph
• Kanban
• Mindmap
• Pie
• Quadrant
• Requirement
• Sequence
• State
• Timeline
• UserJourney

• Architecture
• Block
• Packet
• Radar
• Sankey
• Treemap
• XYChart

Naiad designed by Icons Producer from The Noun Project.