Auto-Dark for Emacs

Do you want Emacs to follow your MacOS/Linux/Windows/Android dark-mode on/off options?

This package, auto-dark-mode, introduces a minor mode in Emacs that enables automatic switching between two user-defined (customizable) themes. This transition occurs seamlessly in response to Dark Mode being enabled or disabled across MacOS, Linux, Windows, and Android platforms.

For now it supports Linux through dbus and Android via Termux.

Installation

Regular Emacs

Install it from MELPA and add to your .emacs or init.el file:

(require 'auto-dark)
(auto-dark-mode)

Or simply copy the auto-dark.el file to ~/.emacs.d/auto-dark/auto-dark.el (or clone this repository there), and then add the following to your .emacs:

(add-to-list 'load-path "~/.emacs.d/auto-dark/")
(require 'auto-dark)
(auto-dark-mode)

Or use use-package to install:

(use-package auto-dark
  :init (auto-dark-mode))

Spacemacs

If you use Spacemacs, add (auto-dark) to the dotspacemacs-additional-packages list and add the following to dotspacemacs/user-config:

(use-package auto-dark
  :init (spacemacs/defer-until-after-user-config #'auto-dark-mode)
  :defer t)

This ensures that auto-dark-mode is activated only after spacemacs's built-in theme loading logic.

Doom Emacs

If you're under Doom Emacs, the following configuration should be enough¹:

;; In your packages.el
(package! auto-dark)

;; In your config.el

(after! doom-ui
  ;; set your favorite themes
  (setq! auto-dark-themes '((doom-one) (doom-one-light)))
  (auto-dark-mode))

Notes for MacOS users

From the box, this package takes advantage of some built-in functionality found on the formulaes Emacs Plus and Emacs Mac to make detecting switches faster.

If you compiled Emacs yourself or used any other pre-compiled binary, it is essential to explicitly instruct auto-dark you want to use Osascript.

You can do this by adding to your configuration:

(setq auto-dark-allow-osascript t)

Doing so will probably make MacOS prompt you for security permissions. If by any chance it does not prompt you, you can check permissions on MacOS by going to:

Settings -> Privacy & Security -> Emacs -> System Events

Also notice if you run emacs from the terminal, Osascript is the only method that will work.

Settings

All provided options, including The light/dark themes can be customized using the Emacs customization system. M-x customize-group auto-dark RET.

You can also take advantage of the hooks auto-dark-dark-mode-hook and auto-dark-light-mode-hook to make it even further customizable. Take a look at this article on how to Integrate Catppuccin with Auto-Dark.

Following, a complete configuration with all settings set to its defaults:

(use-package auto-dark
  :ensure t
  :custom
  (auto-dark-themes '((wombat) (leuven)))
  (auto-dark-polling-interval-seconds 5)
  (auto-dark-allow-osascript nil)
  (auto-dark-allow-powershell nil)
  ;; (auto-dark-detection-method nil) ;; dangerous to be set manually
  :hook
  (auto-dark-dark-mode
   . (lambda ()
        ;; something to execute when dark mode is detected
        ))
  (auto-dark-light-mode
   . (lambda ()
        ;; something to execute when light mode is detected
        ))
  :init (auto-dark-mode))

A short description of each setting:

auto-dark-themes

A list containing two elements. The first is the list of themes to enable when dark-mode is active and the second is the list of themes to enable when dark-mode is inactive.

Possible values for each sublist are themes installed on your system found by customize-themes or nil to use Emacs with no themes (default appearance).

If this variable is nil, then the set of themes from custom-enabled-themes will be used for both dark and light mode. These themes must support frame-background-mode, or else there will be no visible change.

NB: When adding themes to this list, switching between light and dark, or initializing Emacs, you may see a prompt like “Loading a theme can run Lisp code. Really load?” If you answer “yes” and allow Emacs to treat the theme as safe in future sessions, you should only see this prompt once per theme. To disable the prompt completely, you can set custom-safe-themes to t before setting auto-dark-themes.

auto-dark-polling-interval-seconds

The number of seconds between which to poll for dark mode state. Emacs must be restarted for this value to take effect.

This is here for when there's no emacs-plus (MacOS), or emacs-mac (MacOS) or a system with dbus or capable of sending events is found, a timed polling is called to check the current system status.

auto-dark-allow-osascript

Whether to allow function auto-dark-mode to shell out to osascript: to check dark-mode state, if ns-do-applescript or mac-do-applescript.

This is only useful for MacOS, please check the section Notes for MacOS users above.

auto-dark-allow-powershell

Whether to allow function auto-dark-mode to shell out to powershell: to check dark-mode state.

This is only useful for Windows. If not set, it will use the built-in Emacs Windows Registry functions.

auto-dark-dark-mode-hook

List of hooks to run after dark mode is loaded.

You can use this hook to take leverage of auto-dark detection system and issue more elisp code when some state is detected. You can even use only the hooks by setting the themes to nil.

auto-dark-light-mode-hook

"List of hooks to run after light mode is loaded."

You can use this hook to take leverage of auto-dark detection system and issue more elisp code when some state is detected. You can even use only the hooks by setting the themes to nil.

auto-dark-detection-method

The method auto-dark should use to detect the system theme.

Defaults to nil and will be populated through feature detection if left as such. Only set this variable if you know what you're doing!

Screenshots

This package in action:

• macOS (emacs-plus formulae)

• macOS (emacs-mac formulae)

• Linux (Gnome DE)

Footnotes

1. There is possibly an issue with Doom Emacs’ initialization, where the “Loading a theme can run Lisp code. Really load?” prompt can cause initialization to fail. Auto-Dark attempts to ensure that this prompt doesn’t occur during initialization, but it isn’t perfect. If this causes a problem for you, try setting custom-safe-themes to t in your config before setting auto-dark-themes. But be aware that this is a potential security concern. See the documentation of custom-safe-themes for more details. ↩