Bug Report: Error "Keymap file failed to load"

I use NixOS, so things often get put in weird places. In this case, I have a custom keymap (called qr) that does not get stored in /user/share/X11/xkb/. When starting Anki I get this error:

xkbcommon: ERROR: Couldn't find file "symbols/qr" in include paths
xkbcommon: ERROR: 1 include paths searched:
xkbcommon: ERROR:       /usr/share/X11/xkb
xkbcommon: ERROR: Abandoning symbols file "(unnamed)"
xkbcommon: ERROR: Failed to compile xkb_symbols
xkbcommon: ERROR: Failed to compile keymap
[2:35:0717/132940.265534:FATAL:xkb_keyboard_layout_engine.cc(641)] Keymap file failed to load: qr

I can setxkbmap us, launch anki, and then setxkbmap qr, but then I can’t use my custom layout in anki. Similarly, if I setxkbmap "us,qr" -option "grp:ctrls_toggle", then I can launch anki but when I switch the layout it doesn’t apply inside anki.

Isn’t the whole point of keymaps that applications can be agnostic to what keymap you’re using, and just get keysym events?