Markdown document engine: parse, query, lint, build, render, and safely edit Markdown with minimal diffs.

ALTO Markdown converts Markdown to safe HTML and keeps a source-backed document model when an application needs to inspect, lint, or edit content. Use direct conversion for one result; open a document when later work depends on its structure.

<?php

use Alto\Markdown\Markdown;

$html = Markdown::github()->toHtml("# Hello\n\nWelcome.\n");

The conversion returns <h1>Hello</h1> followed by a paragraph containing Welcome.. Raw HTML is escaped and unsafe URL schemes are rejected by default.

Documentation

  • Installation: install the package and verify the runtime.
  • Getting started: render and inspect one document.
  • Conversion: produce HTML or Markdown output.
  • Documents: inspect, query, measure, and edit parsed documents.
  • Quality: lint, fix, and format Markdown.
  • Extensions: choose or create trusted capabilities.
  • Syntax: add authoring syntax.
  • Rendering: control document and HTML output.
  • Resources: resolve imported, included, and embedded content.
  • Security: define input, HTML, and resource boundaries.
  • Errors: catch recoverable failures.
  • Performance: select and measure the correct processing path.
  • Compliance: review supported Markdown specifications.

The core has no runtime Composer dependencies. It supports CommonMark, GitHub Flavored Markdown, and GitHub-oriented documents. Extensions run as trusted application code and receive resource access only through an injected resolver.