I'm told this got fixed in current versions of PureOS, but in case it hasn't: The '\' key didn't work for me out of the box on the Librem 13, but adding the following lines to `/lib/udev/hwdb.d/60-keyboard.hwdb` fixes it:
```
# Purism Librem 13 V2
evdev:atkbd:dmi:bvn*:bvr*:bd*:svnPurism*:pn*Librem13v2*:pvr*
KEYBOARD_KEY_56=backslash
# Purism Librem 13 V3
evdev:atkbd:dmi:bvn*:bvr*:bd*:svnPurism*:pn*Librem13v3*:pvr*
KEYBOARD_KEY_56=backslash
```
#libremquirkfixes