One of my favorite things about my custom mechanical keyboard, is being able to remap the entire key set in the firmware with VIA. I have fn+arrow keys for media, fn+space for play/pause fn+end for calculator, and a bunch of random others. It is so useful I could never get another keyboard that doesn’t have a similar functionality.
> It is so useful I could never get another keyboard that doesn’t have a similar functionality.
I do it at the software level (Linux / Xorg): complete remapping, with an "hyper" key modifier etc.
The reason I do it at the software level is that you can pry my Topre switches from my cold dead hands and the HHKB Pro JP I'm using doesn't have, by default, a programmable controller. Now I know some people mod their Topre keyboards to add a programmable controller but I never got to that point.
Doing so in hardware using .xkb files is... Something. I know way more about .xkb files than I should but, thankfully, so far I've just been able to brink my .xkb file to every new Linux version (supporting Xorg, I'm not on Wayland).
I take at some point I'll look more into how to mod my HHKB keyboards with programmable controller.
I put a Hasu controller[1] in my Leopold F660C (Topre switches) and couldn't be happier. Though it voids the warranty, installation was very easy and it allows total control of the keymap via TMK. Looks like there are similar controllers by Hasu for HHKB[2]. If you can manage to order one I highly recommend it!