EμReader

Previously called The Emacs Reader.

An all-in-one document reader for GNU Emacs, supporting all major document formats. This package intends to take from doc-view, nov.el, and pdf-tools and make them better. And as such, it is effectively a drop-in replacement for them.

EMuReader at Emacsconf 2025

https://media.emacsconf.org/2025/emacsconf-2025-reader–an-introduction-to-the-emacs-reader–divy–main.webm

Supported Formats

EMuReader (via MuPDF) can open all the formats below.

Well-supported Formats

• PDF
• EPUB
• MOBI
• FB2
• XPS/OpenXPS
• CBZ

Office Document Formats

These formats below are not really for document reading, and as such while they are supported by MuPDF and can be opened fine, it’s just not going to be that good of an experience. It should only be used for quickly checking the textual contents of the document, and certainly cannot be edited inside Emacs. (You may use LibreOffice for that.)

Open Document Formats (LibreOffice)

• ODT
• ODS
• ODP
• ODG

Proprietary Formats

Using these formats is heavily discouraged, you should always prefer the above formats from LibreOffice (Which can also you help you edit these formats if you need to). But since MuPDF does come with some very minimal support for these proprietary formats as well, they can also be viewed:

• DOCX
• PPTX
• XLSX

Installation

You can install it from GNU ELPA via M-x package-install RET emureader RET.

Or if you use use-package,

(use-package emureader)

• Dependencies
  • mupdf @ v1.26.0
  • gcc
  • GNU Make

GNU/Linux distribution specific instructions

GNU Guix

guix install emacs-emureader

This will get the latest release of emureader. However, if you want to get latest features, bug fixes (and bugs!) to help us with testing emureader, you should use the master branch. You can instruct Guix to get it for you, like so,

guix install emacs-emureader --with-branch=emacs-emureader=master

You can also upgrade an already installed package with,

guix upgrade emacs-emureader --with-branch=emacs-emureader=master

You may replace the branch name as you need.

Debian GNU/Linux

Follow this write up.

Nix

Follow the instructions here.

MacOS specific instructions

Install MuPDF using Homebrew,

brew install gcc
brew install make
brew install mupdf

Find more information here.

Manual

User lisp directory (recommended)

1. Clone the repository into ~~/.emacs.d/user-lisp/~,

   git clone https://codeberg.org/monadicsheep/emureader ~/.emacs.d/user-lisp/emureader
       

   You may also symlink an existing checkout instead.

2. You may now run M-x prepare-user-lisp RET or restart Emacs to make Emacs automatically prepare and load emureader.
3. You also need to build the dynamic module, for this we provide the M-x emureader-build RET. But you can also run make directly yourself.

package-vc

You can also utilize use-package to do the same, put the following in your configuration,

(use-package emureader
  :vc t
  :load-path "/path/to/emureader")

In emacs -Q

To test emureader in a default Emacs config, first generate the auto loads using make autoloads.

emacs -Q -L . -l emureader-autoloads.el

This command adds the current directory to path, and loads emureader-autoloads.el.

Key Bindings

• n for going to next page
• p for going to previous page
• C-n for scrolling down.
• C-p for scrolling up.
• C-b for scrolling left.
• C-f for scrolling right.
• Q for closing the EMuReader buffer.
• M-< for going to the first page.
• M-> for going to the last page.
• M-g g for going to a particular page.
• M-v or Page Up for scrolling to the top of the page.
• C-v or Page Down for scrolling to the end of the page.
• SPC, S-SPC , and DEL make the above two commands keep scrolling the pages.
• ===, +, and C-<wheel-up> for zooming into the page.
• - and C-<wheel-down> for zooming out of the page.
• H to make the page fit the height of the current window.
• W to make the page fit the width of the current window.

How It Works

This package is entirely distinct from DocView and pdf-tools in both its architecture and implementation. It leverages Emacs’ dynamic/native modules which allows it to interoperate with other programming languages outside of its Emacs Lisp environment.

Thus, we rely on the efficient MuPDF library as a shared object with which our dynamic modules work. All the tasks that require manual memory management, efficiently dealing with the rendered pages, and so on are delegated to the C backend, and Emacs takes care of exclusively what it’s good at: displaying produced pages, buffer management, and all round integration with the rest of Emacs.

For understanding how dynamic modules work within Emacs, please consult the following article I wrote:

https://www.phimulambda.org/blog/emacs-dynamic-module.html

Live Streams

I have been streaming the development of this package on my PeerTube channel: (phi (mu (lambda))).

The streams happen on Sundays, biweekly at around 2:30 PM UTC. Follow the channel on Peertube or my Mastodon to be notified when I stream. You can also find some stream notes here.

If you wish to join the discussion for the package, you should join the IRC channel #phi-mu-lambda on Libera.

License

Unless another license is listed, all files in emureader are licensed under the GNU General Public License version 3 (or at your option, any later version). See COPYING and CONTRIBUTORS for further details.

The logo of the project was made by Divya Ranjan Pattanaik and is shared under CC-BY-SA-4.0. The logo uses the following artworks from GNU:

• A Bold GNU Head by Aurélio A. Heckert
• Icon for Emacs 23 by Kentaro Ohkouchi

The interesting history of different Emacs logos is outlined by Luis Fernandes, in his article on The Design of the Emacs Logo.