[Unit]
Description=Load XModMap keyboard map on X display %I
Documentation=man:xmodmap(1)
After=X11@%i.target
Requisite=X11@%i.target

[Service]
Environment=DISPLAY=%I

Type=oneshot
ExecStart=-/usr/bin/env xmodmap ${XDG_CONFIG_HOME}/X11/modmap

[Install]
WantedBy=X11@%i.target