nizel

Markdown content processor for modern applications.

Custom CommonMark 0.31 parser with frontmatter, templates, filters, elements, plugins, custom blocks, and transforms. No third-party markdown libraries.

Install

npm install nizel

Usage

import { useNizel } from 'nizel';

const processor = useNizel({
  // optional configuration
});

const result = processor.process('# Hello {{ name }}', {
  data: { name: 'World' }
});

Result

process() returns:

• files — output files (HTML by default)
• pages — page metadata from frontmatter
• project — project-level data
• languages — language info

Convenience Methods

processor.parse(markdown);  // AST only, no rendering
processor.render(markdown); // HTML string

Features

• CommonMark 0.31 — full spec compliance (652/652 tests)
• Frontmatter — YAML with arrays, templates, and variable resolution
• Filters — 14 built-in: camel, capital, const, dot, header, kebab, lower, pascal, path, sentence, slug, snake, upper, format
• Elements — customize HTML tags and attributes for any node type
• Templates — {{ variable }} syntax with filter chains
• Plugins — defineNizelPlugin() with beforeParse, afterParse, afterRender hooks
• Custom blocks — defineBlock() for domain-specific content
• Transforms — post-processing pipeline
• Presets — blog, email built-in, or create your own
• Safety — onclick/onerror handlers stripped, javascript: URLs stripped
• TOC — table of contents with level/slug aliases

Options

useNizel({
  data: {},              // template variables
  variables: {},         // alias for data
  preset: 'blog',       // or 'email', or custom object
  slugStyle: 'kebab',   // slug generation style
  elements: {
    a: { tag: 'a', attrs: { target: '_blank' } }
  },
  plugins: [myPlugin()],
  filters: { custom: (v) => v.toUpperCase() },
  blocks: { note: myNoteBlock },
});

Plugins

Official plugins available:

• nizel-plugin-abbr — abbreviation definitions with <abbr> output
• nizel-plugin-alert — GitHub-style and custom alert blocks
• nizel-plugin-autolink — configurable bare URL and email links
• nizel-plugin-citations — citation references and bibliography output
• nizel-plugin-code-copy — copy controls for code blocks
• nizel-plugin-deflist — definition-list syntax
• nizel-plugin-details — disclosure/details blocks
• nizel-plugin-diagrams — Mermaid code block containers
• nizel-plugin-emoji — :name: emoji shortcuts
• nizel-plugin-footnotes — footnote references and definitions
• nizel-plugin-frontmatter-ui — frontmatter metadata rendering helpers
• nizel-plugin-gfm — GFM-oriented plugin preset
• nizel-plugin-heading-anchors — visible anchor links on headings
• nizel-plugin-math — inline and display math wrappers
• nizel-plugin-media — figure, caption, lazy, and responsive image helpers
• nizel-plugin-sanitize — additional rendered HTML sanitizing
• nizel-plugin-shiki — code syntax highlighting via Shiki
• nizel-plugin-task-list — task-list checkbox rendering
• nizel-plugin-toc — rendered [[toc]] table of contents
• nizel-plugin-typography — mark, subscript, and superscript extensions

For native apps or WebViews that need a single browser bundle with a settings-friendly plugin registry, use nizel-kit.

For ready-to-link content styling, use nizel-style. It ships scoped CSS for core rendered content plus optional plugin CSS entrypoints such as nizel-style/plugins/alert.css and nizel-style/plugins/code-copy.css.

License

MIT