Arduix uses chords but QMK has a more advance system it calls combos where it detects keypresses that are pressed sufficiently close together. There are actually layout shifts on top of that as well, so--for example--you can layout shift to "nav mode" and be able to use the arrows as single keypresses. There's a similar mode for using the keyboard as a mouse.

[edit] Here's a link to a reference sheet for Artsey.io, of which Ardux is a fork, it gives you a pretty good idea for how the board is used in practice: https://raw.githubusercontent.com/artseyio/artsey/main/layou...