NIXOS.md

NixOS Installation Guide

This flake provides a NixOS package and module for the Huion Keydial Mini driver.

Installation Methods

Method 1: Using the NixOS Module (Recommended)

Add this to your NixOS configuration (/etc/nixos/configuration.nix or your flake):

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    huion-keydial-mini = {
      url = "github:the3dcoder/KeydialCommander";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { self, nixpkgs, huion-keydial-mini }: {
    nixosConfigurations.yourHostname = nixpkgs.lib.nixosSystem {
      system = "x86_64-linux";
      modules = [
        ./configuration.nix
        huion-keydial-mini.nixosModules.default
        {
          services.huion-keydial-mini.enable = true;
          
          # Add your user to the input group
          users.users.yourUsername.extraGroups = [ "input" ];
        }
      ];
    };
  };
}

Method 2: Direct Package Installation

You can also install just the package without the module:

{ config, pkgs, ... }:

{
  environment.systemPackages = [
    inputs.huion-keydial-mini.packages.${pkgs.system}.huion-keydial-mini-driver
  ];

  # Manually enable required services
  hardware.bluetooth.enable = true;
  services.udev.packages = [
    inputs.huion-keydial-mini.packages.${pkgs.system}.huion-keydial-mini-driver
  ];

  # Add your user to the input group
  users.users.yourUsername.extraGroups = [ "input" ];
}

Post-Installation Steps

1. Copy the default configuration:

   mkdir -p ~/.config/huion-keydial-mini
   cp /etc/huion-keydial-mini/config.yaml ~/.config/huion-keydial-mini/

2. Edit your configuration:

   $EDITOR ~/.config/huion-keydial-mini/config.yaml

3. Enable and start the user service:

   systemctl --user enable --now huion-keydial-mini-user.service

4. Check service status:

   systemctl --user status huion-keydial-mini-user.service
   journalctl --user -u huion-keydial-mini-user.service -f

What Gets Installed

The NixOS module automatically installs:

• ✅ Python package with all dependencies (bleak, evdev, click, pyyaml, dbus-next)
• ✅ Three command-line tools:
  • huion-keydial-mini - Main driver daemon
  • keydialctl - Control utility
  • unbind-huion.sh - Udev helper script
• ✅ Systemd user service (huion-keydial-mini-user.service)
• ✅ Udev rules for device access (automatically patched with correct Nix store paths)
• ✅ Default configuration file at /etc/huion-keydial-mini/config.yaml
• ✅ Documentation and license files

Note: The NixOS module automatically patches the udev rules to use the correct Nix store paths for the unbind-huion.sh script, so everything works out of the box without manual path configuration.

Configuration Files

• System default config: /etc/huion-keydial-mini/config.yaml
• User config: ~/.config/huion-keydial-mini/config.yaml
• Systemd service: /run/current-system/sw/share/systemd/user/huion-keydial-mini-user.service
• Udev rules: /run/current-system/sw/lib/udev/rules.d/99-huion-keydial-mini.rules

Troubleshooting

Service won't start

# Check if bluetooth is enabled
systemctl status bluetooth

# Check if you're in the input group
groups | grep input

# If not, add yourself and log out/in
sudo usermod -a -G input $USER

Permission issues

# Reload udev rules
sudo udevadm control --reload-rules
sudo udevadm trigger

Check logs

# User service logs
journalctl --user -u huion-keydial-mini-user.service -b

# System logs
journalctl -b | grep huion

Development Shell

For development, the flake also provides a dev shell with Python 3.13 and all necessary dependencies:

nix develop

This sets up a Python virtual environment in .venv with all development dependencies.

Building from Source

# Build the package
nix build .#huion-keydial-mini-driver

# Check the flake
nix flake check

# Show package info
nix flake show

Contributing

See CONTRIBUTING.md for development guidelines.