Plugins

Plugins can transform the parsed Semantic AST or the generated Render IR. Multiple plugins run in registration order.

Document transform

import type { MarkdownPlugin } from '@markvia/core'

const addDocumentBadge: MarkdownPlugin = {
  name: 'add-document-badge',
  transformDocument(document) {
    return {
      ...document,
      children: [
        {
          id: 'badge',
          type: 'paragraph',
          position: document.position,
          children: [
            {
              id: 'badge-text',
              type: 'text',
              position: document.position,
              value: 'Generated by a plugin',
            },
          ],
        },
        ...document.children,
      ],
    }
  },
}

IR transform

IR transforms are useful for consistently changing tags, attributes, or node structure:

const addClassName: MarkdownPlugin = {
  name: 'add-class-name',
  transformIR(ir) {
    return {
      ...ir,
      children: ir.children.map((node) =>
        node.kind === 'element'
          ? { ...node, props: { ...node.props, class: 'markvia-content' } }
          : node,
      ),
    }
  },
}

const runtime = createMarkdown({ plugins: [addClassName] })

Plugins should preserve node positions and IDs so editors, incremental updates, and downstream renderers can continue to associate output with the original content.