glu

glu — Markdown to PDF

glu converts Markdown files to PDF. Write your content in Markdown, and glu handles fonts, layout, and page formatting automatically.

glu document.md    # → document.pdf

Installation

Download the latest binaries at https://github.com/speedata/glu/releases/latest.

If you have a Go installation, you can also build from source:

git clone https://github.com/speedata/glu
cd glu
rake build

Quick start

Create a file hello.md:

---
title: Hello World
---

# Hello World

This is a **bold** and *italic* paragraph.

| Column A | Column B |
|----------|----------|
| Value 1  | Value 2  |

Run with:

glu hello.md

This produces hello.pdf — an A4 page with serif fonts, proper headings, and a formatted table. No configuration needed.

Dynamic content with Lua

glu supports embedded Lua for calculations, data processing, and dynamic content. If a file hello.lua exists alongside hello.md, it is loaded automatically:

hello.lua:

function greeting(name)
    return "Hello, " .. name .. "!"
end

hello.md:

# Welcome

{= greeting("World") =}

The {= expr =} syntax inserts the result of any Lua expression. See Markdown mode for the full feature set including Lua code blocks, YAML frontmatter, and custom CSS.

Callbacks

glu provides a callback system for page-level events. For example, drawing a frame on every page:

local frontend = require("glu.frontend")

frontend.add_callback("pre_shipout", "frame", function(doc, page, pagenum)
    -- draw decorations, add page numbers, etc.
end)

Named callbacks can be ordered and removed dynamically. See Callbacks for details.

Documentation

Markdown mode