diff --git a/nixos/desktop/default.nix b/nixos/desktop/default.nix
index 170595ba..b713bfc3 100644
--- a/nixos/desktop/default.nix
+++ b/nixos/desktop/default.nix
@@ -143,6 +143,8 @@ in
       # tramhao/termusic and tsirysndr/music-player does not figure how to use.
       rhythmbox
 
+      evtest # To debug keyremapper as GH-786
+
       # Don't use unstable channel. It frequently backported to stable channel
       #   - https://github.com/NixOS/nixpkgs/commits/nixos-24.05/pkgs/applications/networking/instant-messengers/signal-desktop/signal-desktop.nix
       (signal-desktop.overrideAttrs (prev: {
diff --git a/nixos/hardware.nix b/nixos/hardware.nix
index b8bffe2b..ef89e01f 100644
--- a/nixos/hardware.nix
+++ b/nixos/hardware.nix
@@ -16,7 +16,7 @@
   # Use another filename of "99-local.hwdb"", it is preserved for each host
   #
   # - Specify hardware names even if `evdev:input:*` working for mostcase. I should care both US and JIS layout
-  # - How to get the KEYBOARD_KEY_700??: `nix run nixpkgs#evtest -- /dev/input/event??`
+  # - How to get the KEYBOARD_KEY_700??: `evtest /dev/input/event??`
   # - How to get the hardware name:: `udevadm info --attribute-walk /dev/input/event?? | grep -F 'ATTRS{name}'`
   # - How to apply?: After nixos-rebuild switch `sudo systemd-hwdb update && sudo udevadm trigger`
   environment.etc."udev/hwdb.d/98-keyboards.hwdb".text = ''