mermaid

Generation of diagrams and flowcharts from text in a similar manner as markdown.

Ever wanted to simplify documentation and avoid heavy tools like Visio when explaining your code?

This is why mermaid was born, a simple markdown-like script language for generating charts from text via javascript.

The code below would render the following image

Code	Rendered diagram
graph TD; A-->B; A-->C; B-->D; C-->D;
sequenceDiagram participant Alice participant Bob Alice->>John: Hello John, how are you? loop Healthcheck John->>John: Fight against hypochondria end Note right of John: Rational thoughts <br/>prevail... John-->>Alice: Great! John->>Bob: How about you? Bob-->>John: Jolly good!
gantt dateFormat YYYY-MM-DD title Adding GANTT diagram to mermaid section A section Completed task :done, des1, 2014-01-06,2014-01-08 Active task :active, des2, 2014-01-09, 3d Future task : des3, after des2, 5d Future task2 : des4, after des3, 5d
classDiagram Class01 <|-- AveryLongClass : Cool Class03 -- Class04 Class05 o-- Class06 Class07 .. Class08 Class09 --> C2 : Where am i? Class09 -- C3 Class09 --|> Class07 Class07 : equals() Class07 : Object[] elementData Class01 : size() Class01 : int chimp Class01 : int gorilla Class08 <--> C2: Cool label
gitGraph : options { "key": "value", "nodeWidth": 150, "nodeSpacing" : 150 } end commit branch newbranch checkout newbranch commit commit checkout master commit commit merge newbranch

Installation

CDN

https://unpkg.com/mermaid@<version>/dist/

Replace <version> with expected version number.

Example: https://unpkg.com/mermaid@7.0.4/dist/

Node.js

yarn add mermaid

Further reading

• Usage
• Flowchart syntax
• Sequence diagram syntax
• Mermaid CLI
• Demos

Request for assistance

Things are piling up and I have hard time keeping up. To remedy this it would be great if we could form a core team of developers to cooperate with the future development mermaid.

As part of this team you would get write access to the repository and would represent the project when answering questions and issues.

Together we could continue the work with things like:

• port the code to es6
• adding more typers of diagrams like mindmaps, ert digrams etc
• improving existing diagrams

Don't hesitate to contact me if you want to get involved.

For contributors

Setup

Make sure you have Chrome browser installed, this project uses Chrome headless to running tests.

yarn install

Build

yarn build

If you want real time incremental build:

yarn build:watch

Lint

yarn lint

We use JavaScript Standard Style. We recommend you installing editor plugins so you can get real time lint result.

Test

yarn test

Manual test in browser:

open dist/demo/index.html

Release

Update version number in package.json.

npm publish

Command above generates files into the dist folder and publishes them to npmjs.org.

Credits

Many thanks to the d3 and dagre-d3 projects for providing the graphical layout and drawing libraries!

Thanks also to the js-sequence-diagram project for usage of the grammar for the sequence diagrams. Thanks to Jessica Peter for inspiration and starting point for gantt rendering.

Mermaid was created by Knut Sveidqvist for easier documentation.

Tyler Long has became a collaborator since April 2017.

Here is the full list of the projects contributors.