gleebook

A fast, zero-config static site generator for books and documentation, written in Gleam. Point it at a folder of Markdown files and a SUMMARY.md, and it builds a themed, searchable-by-eye site with a collapsible sidebar, syntax highlighting and live reload — in the spirit of mdBook, but built on Lustre, Wisp and Mist.

Features

• Type-safe generation — every page is rendered through Lustre's typed element tree; there is no string templating.
• Instant watcher & live reload — serve rebuilds when a file in book/ changes and the browser reloads itself.
• Collapsible, resizable sidebar — nested chapters use native <details> accordions; width and collapsed state are remembered per browser.
• Two themes out of the box — Cyberpunk Pink (dark) and Rust Olive (light), with a toggle in the sidebar and a ?theme= URL parameter.
• CommonMark + GFM Markdown — tables, strikethrough, task lists and footnotes are supported.
• Code blocks with a copy button — Gleam is highlighted natively via contour; every other language goes through highlight.js.
• Callouts and embeds — blockquotes render as accented callouts, and a YouTube link in image syntax becomes a privacy-friendly embed.
• Safe by default — raw HTML in Markdown is never emitted into the page.
• Plain static output — the result is a folder of HTML you can host anywhere.

Quick start

Add gleebook to a Gleam project (an empty one is fine — it exists only to host the book):

gleam new my_book && cd my_book
gleam add gleebook@1

Scaffold a book, then serve it with live reload:

gleam run -m gleebook init        # creates book/SUMMARY.md and book/index.md
gleam run -m gleebook serve       # http://localhost:8000

When you're ready to publish, produce the static site:

gleam run -m gleebook build       # writes build/gleebook/

Writing your book

book/SUMMARY.md

The summary defines the book title and the sidebar. The first level-one heading is the title; each list item is a chapter, and indenting by two spaces nests it under the item above.

# My Book

- [Introduction](index.md)
- [Getting Started](getting-started.md)
  - [Installation](getting-started/installation.md)
  - [First Steps](getting-started/first-steps.md)
- [Reference]()
  - [CLI](reference/cli.md)
  - [Configuration](reference/config.md)

An entry with an empty link, like [Reference](), is a label-only group: it appears in the sidebar as a heading for its children but has no page of its own. Chapters can live in subdirectories; the output mirrors the same structure.

Links between pages are written with the .md extension (so they work in your editor and on GitHub) and are rewritten to .html at build time.

Markdown support

Raw HTML blocks are replaced with a warning in the rendered page rather than being passed through.

Theming

The sidebar toggle switches between the two built-in themes and remembers the choice in localStorage. You can also force a theme with a query parameter, which is preserved as you navigate:

index.html?theme=cyberpunk
index.html?theme=olive

To customise colours, create book/custom.css. It is copied into the build and loaded after the built-in styles, so you can override any of the theme variables:

[data-theme='cyberpunk'] {
  --gb-bg: #0b0b12;
  --gb-accent: #7dd3fc;
}

[data-theme='olive'] {
  --gb-accent: #b45309;
}

Variables available on both themes:

Any other CSS works too — the content column carries the gleebook-prose class, so .gleebook-prose h2 { … } is a safe hook.

Project layout

my_book/
├── gleam.toml
├── assets/              # static files, copied to build/gleebook/assets/
├── book/
│   ├── SUMMARY.md       # title + sidebar structure
│   ├── custom.css       # optional theme overrides
│   ├── index.md
│   └── ...
└── build/
    └── gleebook/        # generated site (git-ignore this)
        ├── index.html
        ├── assets/
        └── ...

Deploying

build/gleebook/ is a self-contained static site. Deploy it like any other: GitHub Pages, Netlify, Cloudflare Pages, an S3 bucket, or a plain web server. Links are relative, so the site works from a sub-path as well as from a domain root.

CLI reference

build exits with an error summary if any chapter listed in SUMMARY.md has no matching Markdown file; a placeholder 404 page is generated in its place so the rest of the site still builds.

Requirements

• Gleam 1.13 or later
• Erlang/OTP 28 or later

Development

gleam build            # Build the project
gleam test             # Run the tests
gleam run -m gleebook serve   # Dogfood the docs in ./book

Further documentation can be found at https://gleebook.hexdocs.pm/.

Licence

MIT — see LICENCE.