Portable documents and feeds. Normalize HTML, Markdown, MDX, or JSON and render it through a host Chakra system.

Use @postkit/core when an API or feed needs to offer the same article as HTML, Markdown, MDX, or versioned JSON. The package has no React dependency.

import { parsePostkit, serializePostkit } from '@postkit/core';

const document = parsePostkit(input, { format: 'html' });

return {
  html: serializePostkit(document, { format: 'html' }),
  markdown: serializePostkit(document, { format: 'markdown' }),
  json: serializePostkit(document, { format: 'json' }),
};

The HTML parser keeps safe semantic structure and strips scripts, event handlers, presentation attributes, and executable URLs. The safe MDX parser accepts literal component tags but rejects expressions, spread props, imports, and exports. JSON input must match the current versioned document schema.

Task lists retain checked and unchecked state through HTML using disabled checkboxes. Markdown exports escape literal block markers, entities, and link destinations to preserve their meaning. Footnotes are portable: [^id] and :footnote[…] become footnoteReference and footnoteDefinition nodes, numbered by first reference. HTML gets linked marks and an end list with backlinks (ids prefixed by footnotes.scope), plain text gets [1] marks and a numbered list, and a reference with no definition fails with its line and column.

Render through Chakra

@postkit/chakra/document supplies DocumentRenderer. Semantic input is mapped through Postkit's Chakra-backed prose primitives, so the host's Heading, List, Table, Image, Code, and other recipes continue to apply.

import { DocumentRenderer, parsePostkitHtml } from '@postkit/chakra/document';

const document = parsePostkitHtml(rssItem.content);

<PostkitProvider system={siteSystem}>
  <DocumentRenderer
    document={document}
    components={{
      a: SiteLink,
      img: FeedImage,
    }}
  />
</PostkitProvider>;

The renderer never creates arbitrary elements or invokes unknown components. Unknown nodes are unwrapped by default, retaining readable children. Use the unknownElements and unknownComponents props to drop them instead.

Reconstruct rendered output

DocumentRenderer's component views load the first time a document renders them, so a page downloads only the views its document uses. A server render that waits for Suspense (as Next.js does) has them in its HTML; for a synchronous render, pass components={postkitChakraViews}.

HTML serialization and DocumentRenderer emit versioned data-postkit-* annotations by default. They identify semantic nodes, rich component names, and JSON-compatible component props without requiring an extra layout wrapper. parsePostkitHtml recognizes those hints, while also remaining useful for ordinary unannotated RSS or CMS HTML.

Annotations improve round trips, but they are not an authenticity mechanism. Continue to treat remote content as untrusted and expose only application- approved component overrides and link behavior.