A little while back, I bought a new, ergonomic keyboard called the Kinesis Freestyle2. In tandem, I installed Karabiner so that I can really customize the keyboard. Ultimately, I had found a great set up where my hands could relax on the keys all day – even had the mouse motion and clicks mapped!

All was good, or so it seemed…

One huge pet peeve I’ve developed about the Kinesis Freestyle2 is where the left-hand “command” button is… I use it frequently, switching through applications (command+tab, command+backtick), copying and pasting (command+c, command+v), exiting and creating tabs in Chrome (command+w, command+t), and on and on and on! Unfortunately, the Freestyle2 has a huge left-hand spacebar that I never use (right or wrong, this job is pretty exclusive to my right hand); this spacebar real estate means that the left-hand command button is pushed very far left, making for some pretty awkward left-hand thumb stretches… I could get used to awkward, but this further unleased hell and fury: my left hand and arm have become weak and unresponsive!

Ok, no big deal, right? This is where Karabiner comes in. Just map that key somewhere else!

Few things: (1) there is the petulant “but I don’t want to” feeling. Oh well, no choice really. (2) I’ve already customized my keyboard quite a bit – where is left to map it?

In my original set up, I had the escape key mapped to the caps_lock key. I really liked this…but it seemed like the most obvious place to map the left-hand command key to: it’s easy to access and I use the left-hand command key way more than escape.

Done!

Or was I? Now, any time I needed escape, I was reaching to its original, way far off location… Not ideal!

But now I was really in a bind: I really didn’t have any keys left for one of Karabiner’s simple mappings… I needed to create a custom “complex mapping.” So I had to learn a bit!

Karabiner Complex Mappings

First thing to know is where these are located:

cd ~/.config/karabiner/assets/complex_modifications/

Next, if you already have some complex modifications installed from the website, you can see how it’s done. For example, I have “Vi mode [left_control + hjkl]” and “Mouse Keys Mode 4 (rev 1)” installed, which I found saved as JSON files 1554824774.json and 1554846562.json, respectively. Looking through those, I learned how to create my own (shown below).

ls
  1554824774.json   1554846562.json

Basically, I had to think, “What key combo do I never use?” Answer: shift + shift. This is also easy on the hands to perform. Great! One thing I found is that in the JSON file, there is a primary key and modifier key – so you can technically make this mapping as “hold on left shift, then press right shift” or the other way around. What I did was use both so it works either way.

{
  "title": "Shift, shift, escape!",
  "rules": [
    {
      "manipulators": [
        {
          "description": "Esc = L-shift + R-shift",
          "from": {
            "key_code": "left_shift",
            "modifiers": {
              "mandatory" : [
                "right_shift"
              ]
            }
          },
          "to": [
            {
              "key_code": "escape"
            }
          ],
          "type": "basic"
        },
        {
          "description": "Esc = R-shift + L-shift",
          "from": {
            "key_code": "right_shift",
            "modifiers": {
              "mandatory" : [
                "left_shift"
              ]
            }
          },
          "to": [
            {
              "key_code": "escape"
            }
          ],
          "type": "basic"
        }
      ]
    }
  ]
}

As a last note, I had my directional keys mapped to mouse motions, but wasn’t using them since I’ve since installed the complex mapping “Mouse Keys Mode 4 (rev 1)” from the website. I found that having caps_lock mapped to command is pretty good, but not perfect – there were still some awkward finger motions involved. So I mapped all the directional keys to command as well, and getting used to all of it…

We’ll see how it goes. So far, if today serves as a good metric, then things are looking good! My fingers, wrists, and forearms are all feeling fine :-)

Some RSI References

Repetitive stress energy [RSI]. It sucks. Learn more!

• https://www.osha.gov/SLTC/etools/computerworkstations/checklist.html
• https://www.amazon.com/Carpal-Syndrome-Therapy-Computer-Professionals/dp/0965510999/ref=sr_1_1?ie=UTF8&s=books&qid=1265169572&sr=8-1
• https://web.eecs.umich.edu/~cscott/rsi.html