Keyboard Daemon

This is a pretty simple program that monitors layout switching in the OS/display server/window manager/desktop environment and pushes commands to all connected and identified ZSA keyboards (ErgoDox, Moonlander, Voyager, etc.) to switch to the corresponding layer.

The mapping can be passed as arguments when launching the program - they will be treated as 0-indexed layer mapping, so something like en ru will be treated as:

• en = layer 0
• ru = layer 1

If you need to skip a layer (e.g. make a mapping Norwegian - layer 0, English - layer 2) then just use any character sequence that isn't part of any of your locales (no - en works, and no oeinnhvtsatsafatrstarsta en does too). The matching is done as case-insensitive prefix matching, so for most double-locale setups you can use a single letter (f e for French and English, for example).

GNOME Note: GNOME Wayland strictly uses XKB layout shortcodes (e.g., us, ru, fr) instead of full display names. If you use GNOME, pass 'us' instead of 'en' to correctly map your layouts!

MacOS NOTE: MacOS is unique in the way they treat locales, so you should use the shortest unique substring for it instead of shortest unique prefix.

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Installation

You can either download a pre-compiled release for your OS or build from source.

Option 1: Pre-compiled Release (Recommended)

1. Download the latest .zip release for your architecture and OS (Windows version is compiled solely against x86_64, as it will work on arm too) from the GitHub Releases page and extract it;
   1. MacOS only Open your terminal and navigate to the extracted folder;
   2. MacOS only Remove the Apple quarantine flag by running: xattr -cr .
2. Navigate to the extracted folder and run the included installation wizard from your terminal:
   • Linux: ./install_linux.sh
   • macOS: ./install_mac.sh
   • Windows: Right click install_win.ps1 and select "Run with PowerShell" (or run it via terminal);
3. The interactive wizard will prompt you for your platform/layout arguments, copy the binary to your local app data, and automatically register it to start silently in the background.

Option 2: Build from Source

If you are adapting the daemon for your own needs, you can easily compile and install it using make.

Arch Linux Note: A standard PKGBUILD is included.

git clone https://github.com/Veitangie/keyboard-daemon.git
cd keyboard-daemon
makepkg -s
sudo pacman -U kbd-daemon-<platform>-git-*.pkg.tar.zst

Replace <platform> with one of: hyprland, gnome, plasma, sway, x11. Don't forget to enable the service with systemctl --user enable --now kbd-daemon-<platform>

1. Clone the repository.
2. Run the make target for your specific display server or OS:
   • Linux: make hyprland, make gnome, make plasma, make sway, make x11
   • macOS: make macos
   • Windows: make win
3. The interactive installer will launch automatically.
4. If you wish to bypass the interactive prompts, you can pass your layout directly: make hyprland en ru

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On Code Quality

This codebase was initially written in about 24 hours from start to finish by a person who has never written a single line of code in a language without managed memory, much less in C. It has since had some work done on it, but the total development time spent is still less than 30 hours total. This means that the codebase is a mess by any standard, but what's important is that it works, therefore I'm leaving it as is. However, for future updates if one ever comes, here's a known list of improvements:

1. Parser in linux_hypr/parser.c seems pretty convoluted for the task, and while it is robust enough as an algorithm, it would be better represented as a table-driven state machine to remove the goto jumps;
2. Start using fixed-length buffers (bounded by PATH_MAX) or heap allocations for file paths instead of variable length arrays to prevent potential stack smashing;
3. Add bounds checking to the Unix domain socket path in main.c. strcpy into sockaddr_un.sun_path risks a buffer overflow if the user's XDG_RUNTIME_DIR exceeds 108 bytes;
4. Extract magic numbers (like the 33-byte HID write chunks or the 0x06 0x60 0xFF device signatures) into readable #define macros;

Support & Contributing

The feature set of this tool is intentionally very tight and tailored to personal needs.

You (all two of you other ZSA keyboard users who need different layouts for different locales, and of course you, Greg) are welcome to open Issues or Pull Requests if you run into problems or have improvements, but please note that this is a personal project and I cannot guarantee they will be reviewed, fixed, or merged.

Platform Support Note: The main target for me personally is Voyager on Linux with Hyprland and on MacOS, so I can't guarantee that I will be able to help you with other platforms or keyboards, but they should likely work. The binary still remains to be tested on X11, all other platforms had some manual testing done. Valgrind showed no leaks in any of the Linux variants that were tested even under unusual hotplugging, layout switching and layout list changing behaviors. As for the install scripts - some of them may still act up, but that will probably be fixed in a future release. And finally, the tool has dependency on systemd on Linux, so if you happen to use anything else - install scripts won't work for you. But you probably already know how to write a systemd service analogue in your system.

Feel free to fork the repository under the terms of the GNU GPLv3 license!