x11-set-keyboard-option.sh

vm=$(nix-build --no-out-link - <<'EOF'
(import <nixpkgs/nixos> {
configuration = { pkgs, lib, ... }: with lib; {
  users.users.me.isNormalUser = true;
  services.xserver = {
    enable = true;
    desktopManager.xterm.enable = true;
    displayManager.lightdm = {
      enable = true;
      autoLogin.enable = true;
      autoLogin.user = "me";
    };
    displayManager.sessionCommands = ''
      keyboardId=$(
        ${pkgs.xorg.xinput}/bin/xinput |
          sed -nE 's/.*?Virtual core keyboard.*?id=([0-9]+).*?master keyboard.*/\1/p'
      )
      if [[ $keyboardId ]]; then
        ${pkgs.xorg.setxkbmap}/bin/setxkbmap -device $keyboardId -option caps:swapescape
      fi
    '';
  };
};
}).vm
EOF
)
export NIX_DISK_IMAGE=/tmp/vmimg; rm -f $NIX_DISK_IMAGE; QEMU_OPTS='-m 1024 -smp 3' $vm/bin/run-*-vm