mdbook-rss-feed

An mdBook preprocessor that generates a beautiful RSS 2.0 feed (and optional Atom) for your book, with HTML previews for each chapter.

Perfect for blogs, documentation sites, or any mdBook that you want to publish.

Features

HTML preview in <description> built from the first paragraphs of each chapter
Hybrid preview source:
- Prefer chapter body content for the preview
- Fall back to description in frontmatter when the body is empty or very short
Proper XML escaping via the rss crate
Falls back to file modification time if no date in frontmatter
Supports date: in YAML frontmatter (RFC3339 or YYYY-MM-DD)
Respects config.book.title, config.book.description, and output.html.site-url
Zero-config, just drop it in book.toml
Works with or without YAML frontmatter

Installation

cargo install mdbook-rss-feed

Version Check:

mdbook-rss-feed --version

Tested against:

mdBook v0.4.40 & v0.5.1
Rust editions 2020 & 2024

Usage

After installing globally, add the following to your mdbook's book.toml:

[book]
title = "your-title"
author = "your-author"
language = "your-lang"
src = "src"

[preprocessor.rss-feed]
renderers = ["html"]

[output.html]
site-url = "https://your-user.github.io/"

renderers = ["html"] ensures the preprocessor only runs for HTML builds.

If you omit title, mdBook will use My mdbook.
If you omit site-url, the default is https://example.com. Set this to the public base URL of your site.
With the example above, the feed would be at: https://your-user.github.io/rss.xml.

Frontmatter

Frontmatter is optional. Without it, entries only include the chapter title, book name, and date/time.(varies by RSS reader)

With frontmatter, you can customize those fields and add author and description:

title: Debugging NixOS modules
date: 2025-11-22
author: saylesss88
description: This chapter covers debugging NixOS modules, focusing on tracing module
options and evaluating merges.

How feed preview is generated

The preview is generated from the rendered HTML of the chapter. The crate finds <p>…</p> blocks and takes the first 2–3 paragraphs, up to 800 characters.

If a chapter starts with non-paragraph content (lists, details blocks, custom markup), the preview starts at the first real paragraph.

To override this, set description in the YAML frontmatter; that text is used when the body is empty or very short.

Default: preview comes from the first few body paragraphs.
Fallback: when the body is empty/very short, preview comes from description.

If you never want to use the fallback, just omit description; the preview will always come from the body.

Hiding frontmatter in the rendered HTML

mdBook does not parse or strip YAML frontmatter, so the raw block (e.g. any YAML keys like title:, date:, etc.) appears in the HTML.

To avoid this, you can use:

mdbook-frontmatter-strip

RSS Button for mdbook header

Your book.toml can accept additional css and js:

additional-css = [ "theme/rss-button.css" ]
additional-js = [ "theme/rss-buttons.js" ]

In your books theme/ directory, place these two files:

theme/rss-button.css

/* Simple RSS header button */
.rss-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  margin-left: 8px;
  color: var(--sidebar-fg, #333);
  opacity: 0.7;
  transition: opacity 0.2s;
}

.rss-btn:hover {
  opacity: 1;
  color: var(--sidebar-fg, #333);
}

/* Optional: orange hover like classic RSS */
.rss-btn:hover svg {
  stroke: #f26522;
}

theme/rss-button.js

document.addEventListener("DOMContentLoaded", () => {
  const menuBar =
    document.querySelector(".menu-bar .right-buttons") ||
    document.querySelector(".menu-bar");
  if (!menuBar) return;

  const rssLink = document.createElement("a");
  rssLink.href = "https://your-user.github.io/rss.xml"; // set to your feed URL
  rssLink.target = "_blank";
  rssLink.rel = "noopener";
  rssLink.title = "Subscribe to RSS feed";
  rssLink.className = "rss-btn";

  rssLink.innerHTML = `
    <svg xmlns="http://www.w3.org/2000/svg"
         width="16" height="16" viewBox="0 0 24 24"
         fill="none" stroke="currentColor" stroke-width="2"
         stroke-linecap="round" stroke-linejoin="round"
         style="margin-bottom:-3px">
      <circle cx="6" cy="18" r="3"></circle>
      <path d="M6 6c6.627 0 12 5.373 12 12"></path>
      <path d="M6 12c3.314 0 6 2.686 6 6"></path>
    </svg>
  `;

  const printButton = menuBar.querySelector(".print-btn, #print-button");
  if (printButton && printButton.parentNode === menuBar) {
    printButton.before(rssLink);
  } else {
    menuBar.appendChild(rssLink);
  }
});

Now you should have a small logo pinned to the top right of your book that leads to https://your-site/rss.xml

License

Apache License 2.0

mdbook-rss-feed 0.2.4