Pretty snappy. All the gnome APIs are written in C. It doesn’t run on node, it runs on gnome-javascript (gjs) which exposes all the C APIs through JavaScript. If you use the Astal wrappers its pretty painless but using the gnome APIs directly in gjs is a little weird since you have to consider things like memory management.

I have it activate a layer when held where all the other keys are remapped.

I also use a 45% keyboard (https://wilba.tech/jd45) and its done in the keyboard’s firmware (https://qmk.fm/), so I need the extra keys.

I have an older model of the JD45 with a full bottom row.

It is gnome, but https://aylur.github.io/astal/showcases/ is pretty awesome if you’ve done any React development. Pretty much coded up my own desktop environment with typescript and tsx for layout stuff. Lot’s of fun widgets.

Note that I use nixos so pretty much everything is hand picked instead of a prebuilt ready to go environment. Hyprland for the basic desktop, Astal for my desktop shell with widgets, toolbars, etc.