Using sticky modifier keys

Update I ended up not liking this as much as I thought, mainly because there is no way to undo accidental key presses. I could see myself keep using sticky modifiers if there was a way to define a timeout.

Original post

My workflow is pretty much a 100% keyboard driven, between Emacs and my Window Manager I use a lot of modifier keys. While having a keyboard like the Kinesis Advantage helps a great deal in reducing the gymnastics your fingers have to perform I decided to try and optimize my workflow further using sticky modifier keys and I'm very happy with the result.

If you already have a keyboard with easily accessible modifiers, making them sticky is like having motions in Emacs similar to vim, except all your motions start with a modifier on your thumb cluster. It takes some getting used to but I definitely think it's worth a try if you are an Emacs user.

Depending on your system there are multiple ways to achieve this. For GNU/Linux systems running Xorg there is a tool called xkbset which allows you to set various features of XKB (X keyboard extension).

Here's how to enable sticky modifiers using xkbset.

xkbset sticky -twokey -latchlock
xkbset exp 1 =sticky

By default pressing two keys at the same time disables sticky keys, we want to disable this using -twokey.

Pressing a modifier twice locks it, for example, pressing shift twice would basically act as caps lock. This could be nice but I decided to disable it using -latchlock argument.

Finally xkbset exp 1 =sticky makes it so the sticky keys don't expire.

I feel like this in combination with my custom repeat keymaps using the built-in repeat-mode has greatly improved my Emacs experience.