Runtime support

The core entry (sfn-diagram) builds SVG with a DOM-free string renderer, so generateSvg, generateMermaid, generateDiagram, and generateFromAwsResponse run in Node, browsers, and edge runtimes (Cloudflare Workers, Vercel Edge, Deno, Bun) with no DOM polyfill.

PNG export (sfn-diagram/png), the CLI, and CI/PR integration building blocks (sfn-diagram/ci — used by the GitHub Action and the sfn-diagram comment gitlab CLI subcommand) are Node-only — they rely on a native rasterizer (@resvg/resvg-js), Node’s filesystem, or (for sfn-diagram/ci) shelling out to git and, optionally, @aws-sdk/client-sfn for execution overlays. Because @resvg/resvg-js and @aws-sdk/client-sfn are optional peer dependencies, install them alongside sfn-diagram when you need PNG output or execution overlays; exportPng throws an actionable error if @resvg/resvg-js is missing.

sfn-diagram/png also ships an opt-in engine: 'html-to-image' fallback backed by the node-html-to-image peer, for cases that need its headless-Chromium rendering instead of the native rasterizer. It is a library-only option — the CLI and Docker image always use @resvg/resvg-js and have no engine flag.

Node versions: core, the CLI, and PNG export via the default resvg engine all require Node >= 20. Only the opt-in html-to-image engine raises that floor, to Node >= 22.12.0, set by node-html-to-image v6.

// Works in Node, browser, and edge:
import { generateSvg } from 'sfn-diagram';

// Node-only:
import { exportPng } from 'sfn-diagram/png';
import { runGitlabComment } from 'sfn-diagram/ci';