KMonad config to turn a ThinkPad X240 keyboard UHK alike. Combined with .Xmodmap for german umlauts and fixed ins/end shenanigans.

.Xmodmap

! Fix ThinkPad shenanigans
keycode 118 = End
keycode 115 = Insert

! AltGr is Mode_switch
clear mod5
keycode 108 = Mode_switch

! AltGr shortcuts for umlauts
keycode 39 = s S ssharp
keycode 38 = a A adiaeresis Adiaeresis
keycode 30 = u U udiaeresis Udiaeresis
keycode 32 = o O odiaeresis Odiaeresis
keycode 26 = e E EuroSign EuroSign
keycode 49 = grave asciitilde degree
keycode 57 = n N ntilde Ntilde

x240_uhk.kbd

#|                            UHK on an X240
 |
 | KMonad configuration for a ThinkPad X240 with an ANSI keyboard, using a US
 | layout as a base. Roughly emulates an Ultimate Hacking Keyboard's mod layer.
 |
 | Space is mapped as a tap-space/hold-mod key. Alternatively, Capslock is also
 | remapped as mod key. Currently only arrow keys, home, end, del and page up/down
 | are mapped on the mod layer.
 |
 | Template for a new layer:
 |
 | (deflayer name
 |
 |                                                                         _
 |   _    _    _    _    _    _    _    _    _    _    _    _     _   _    _    _
 |   _    _    _    _    _    _    _    _    _    _    _    _     _        _
 |   _    _    _    _    _    _    _    _    _    _    _    _     _        _
 |   _    _    _    _    _    _    _    _    _    _    _    _              _
 |   _         _    _    _    _    _    _    _    _    _    _              _
 |        _    _    _              -              _    _    _         _    _    _ 
 |                                                                    _    _    _ 
 | )
 |
 | Author: @foosel
 | based on https://github.com/david-janssen/kmonad/blob/master/keymap/user/slotThe/x220-iso-us-colemak-dh-z.kbd
 |
 |#

(defcfg
  input (device-file "/dev/input/by-path/platform-i8042-serio-0-event-kbd")
  output (uinput-sink
          "KMonad: X240"
          "sleep 0.2s; xset r rate 230 70; sleep 0.2s; setxkbmap -option compose:menu")
  cmp-seq compose            ;; looks odd, but with compose:menu this HAS to be compose, not menu
  fallthrough true           ;; we don't want to have to worry about all the Fn stuff
)


(defalias
  mod (layer-toggle mod)     ;; Switching to the UHK mod layer
)

(defalias
  smh (tap-hold 200 spc @mod)    ;; Space     when tapped, mod toggle when held
  tmd @mod
)

(defsrc
                                                                        end
  esc  f1   f2   f3   f4   f5   f6   f7   f8   f9   f10  f11   f12 home ins  del
  grv  1    2    3    4    5    6    7    8    9    0    -     =        bspc
  tab  q    w    e    r    t    y    u    i    o    p    [     ]        \
  caps a    s    d    f    g    h    j    k    l    ;    '              ret
  lsft      z    x    c    v    b    n    m    ,    .    /              rsft
       lctl lmet lalt           spc            ralt prnt rctl      pgup up   pgdn
                                                                   left down rght
)

(deflayer qwerty
                                                                        end
  esc  f1   f2   f3   f4   f5   f6   f7   f8   f9   f10  f11   f12 home ins  del
  grv  1    2    3    4    5    6    7    8    9    0    -     =        bspc
  tab  q    w    e    r    t    y    u    i    o    p    [     ]        \
  @tmd a    s    d    f    g    h    j    k    l    ;    '              ret
  lsft      z    x    c    v    b    n    m    ,    .    /              rsft
       lctl lmet lalt           @smh           ralt prnt rctl      pgup up   pgdn
                                                                   left down rght
)

(deflayer mod
                                                                        _
  _    _    _    _    _    _    _    _    _    _    _    _     _   _    _    _
  _    _    _    _    _    _    _    _    _    _    _    _     _        _
  _    _    _    _    _    _    pgup home up   ins  del  _     _        _
  _    _    _    _    _    _    pgdn left down rght _    _              _
  _         _    _    _    _    _    _    _    _    _    _              _
       _    _    _              _              _    _    _         _    _    _ 
                                                                   _    _    _ 
)