Post

07 - Configure Karabiner-Elements in macOS

What is karabiner-elements and how to configure the mappings

  • Karabiner-elements is a powerful and stable keyboard customizer for macOS.
  • NOTE: After installing karabiner, you’ll notice that the windows are all over the place, I want to keep my windows organized, so will configure and install a window manager, in my case yabai in a future video. That will enable the transparency effect on my terminal and other apps
  • NOTE: GokuRakuJoudo is a famous karabiner.json manager, similar to what we will do here, but using the edn file format instead of typescript. I don’t have the time or will to set it up, as my current configuration works fine for me. But if someone can explain the benefits over this approach it would be appreciated

Install and configure Karabiner-Elements

  • First, we’ll install the package so its easier to understand how it works
    • Then I’ll explain what karabiner is, and what its used for
1
brew install --cask karabiner-elements
  • Open the karabiner-elements app
  • Permissions window will popup, give the required permissions to both
    • karabiner_grabber
    • karabiner_observer
  • I set up my mappings using the repo below
    • https://github.com/mxstbr/karabiner
    • This repo translates from manageable typescript code rules.ts (400 lines) to the karabiner configuration file karabiner.json (2500 lines)
    • Is this repo needed? No, but it’s way easier to manage the mappings
  • Karabiner will automatically load the configuration we set up in the dotfiles video ~/.config/karabiner/karabiner.json
  • So mappings will start working automatically after installing it
  • All my mappings can be found in the dotfiles directory (demo in video)
    • Alacritty hyper+space+j
    • Safari hyper+space+k
    • Obsidian hyper+space+o
    • Chatgpt hyper+space+;
      • Add it to dock in chrome, can also use safari, doesn’t matter
    • Spotify hyper+space+h
    • Youtube hyper+space+y
      • Add it to dock in chrome, can also use safari, doesn’t matter
    • System settings hyper+space+'
    • Visual Studio code hyper+space+n
    • Finder hyper+space+f
    • I have additional mappings to:
      • Navigate between tabs in my browsers
      • Increase volume up/down
      • Increase screen brightness up/down
      • Open raycast extensions
      • Execute BetterTouchTool commands
      • And much more (demo in the video)
    • If you don’t have one of the apps installed, the mapping does nothing

  • I like switching my raycast hotkey to hyper+g
  • I also like configuring the paste app to use hyper+w

configure automatic typescript to json translation

  • All my mappings are statically configured at the moment, but you may not want to keep those, as I guess you’ll configure your own
    • So that’s what we’re doing below. Every time the rules.ts file is updated we want that those changes are automatically applied to the karabiner.json file, so we use the mxstbr repo we saw above
    • Demo on how the file doesn’t change automatically at the moment
  • So we install dependencies and run the build
1
2
3
4
5
6
7
8
9
10
11
# Make sure to change to the mxstbr project directory
cd ~/github/dotfiles-public/karabiner/mxstbr

# Installs the project dependencies. These dependencies are usually defined
# in a package.json file in the root directory of the TypeScript project.
# This is a one-time setup step unless the dependencies change.
yarn install

# This runs the `scripts` section in the `package.json` file
# Compiles the TypeScript code into a karabiner.json file based on the rules.ts file
yarn run build
  • Every time we make a change to the rules.ts file, we have to run the yarn run build command to translate the changes to the karabiner.json file but running the build command every time would be extremely annoying, so we run a watch command which will run the build automatically if changes occur
1
yarn run watch
  • That’s a bit better, but we would have to manually run that watch command every time we are working with the mappings so that it applies the changes
  • Instead, I want to run this watch command when the computer starts, so we have to create a LaunchAgent plist file
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
cat <<EOF >~/Library/LaunchAgents/com.linkarzu.karabiner.plist
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
    <string>com.linkarzu.karabiner</string>
    <key>ProgramArguments</key>
    <array>
      <string>/opt/homebrew/bin/yarn</string>
      <string>run</string>
      <string>watch</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>StandardOutPath</key>
    <string>/tmp/karabiner_linkarzu.out.log</string>
    <key>StandardErrorPath</key>
    <string>/tmp/karabiner_linkarzu.err.log</string>
    <key>WorkingDirectory</key>
    <string>$HOME/github/dotfiles-public/karabiner/mxstbr</string>
    <key>EnvironmentVariables</key>
    <dict>
      <key>PATH</key>
      <string>/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/opt/homebrew/bin</string>
    </dict>
  </dict>
</plist>
EOF
  • Notice the file was created
1
cat ~/Library/LaunchAgents/com.linkarzu.karabiner.plist
  • Now that the file is created, I need to run it
    • If you don’t get any warnings, that’s a good sign
1
launchctl bootstrap gui/$(id -u) ~/Library/LaunchAgents/com.linkarzu.karabiner.plist
  • Now I’ll modify the rules.ts file, and changes will be applied automatically
  • Just leave this running and you should be good

  • If for any reason, you need to unload or stop this plist from running, run the command below, but keep in mind that the changes wont be automatic anymore
  • You can also delete the plist file if needed
1
launchctl bootout gui/$(id -u) ~/Library/LaunchAgents/com.linkarzu.karabiner.plist

  • To see the error and log files we created below
1
cat /tmp/karabiner_linkarzu.out.log
1
cat /tmp/karabiner_linkarzu.err.log
This post is licensed under CC BY 4.0 by the author.