Four output formats
SVG, Mermaid, standalone HTML, and PNG from one definition. SVG is built DOM-free, so it renders anywhere JavaScript runs.
sfn-diagram
Turn any Step Functions state machine into a diagram — in Node, the browser, an edge runtime, your editor, or a pull request.
Reads more than raw ASL
Point it at an ASL file, a CloudFormation/SAM/CDK template, a Terraform config, or a live state machine fetched through the AWS SDK.
Diff and execution overlays
Highlight what changed between two revisions, or colour a diagram by what actually happened in a run.
An ecosystem, not just a library
A CLI, a VS Code extension, a React component, and a GitHub Action that comments diagrams on pull requests.