I am a programmer by trade and suffer from the beginning stages of RSI. As a programmer, I use letters, symbols and cursor navigation most often. To prevent strange finger gymnastics, I wrote a script to rank which non-letter characters occurred in my primary source projects most often and then placed these characters in the easiest to reach locations, within reason and for me. I made heavy use of momentary layer toggling.
The key mapping is made up of 5 layers: Letters, Symbols, Navigation, Numbers, and Function Keys.
The layout can be viewed visually at:
http://www.keyboard-layout-editor.com/#/gists/319474e5e2d199e583371ed1d2aec316
The keys have multiple symbols:
The symbols in the layout editor are not entirely clear.
The Z and ? keys double as shift keys. Hold for a shift, tap for a Z or ?
The bottom row from left to right:
The letter layer is separated by 2 center rows of keys. This spreads the hands out a little further which helps not twist the wrists as much. The 2 center rows are [], (), [], and Ctrl and Alt keys.
The symbol layer keys are accessed by the thumbs. They are the closest to the thumbs, instead of the number toggle, because in my code I found I used symbols much more often than numbers. There are two symbol layer keys because the symbols spread across the right and left half of the keyboard. Thus, some symbols are easier hit with the left hand modifier or right hand modifier.
The number layer key is only accessible by the left thumb because all of the number keys are on the right side of the keyboard. When in the number layer, you can press the key to the right to make that layer sticky when you are going to do a lot of number entry.
The function layer key is only accessible by the left thumb because all of the function keys are on the right side of the keyboard.
The navigation layer key is only accessible by the right thumb because all of the navigation keys are on the left side of the keyboard. You can press the key to the right of the navigation layer to make the navigation layer sticky when you are doing a lot of navigation, reading a web page for example.
When using the number or navigation layers, the same hand that accesses the momentary layer toggle key also has the 4 primary modifiers under their home row.
This is so you can easily press Cmd+Shift+F4 or when navigating, select text or words of text by pressing Shift+Control, for example.
Some keys are duplicated. For example, () are available in easy to reach locations while in the Number layer because they are often used in math.
The symbol layer has additional helpers for programming including a single keys that enter /=, *=, -=, +=, !=, <>, ||, and &&. It also includes three special Return keys on the left:
I have been using the keymap for some time now and believe it to be a good keymap. There are a few things through the week that I wonder if it would have been better if this key were moved to that location.
This keymap may change for further optimization.
I am very interested in your feedback. Send me a message here on GitHub, r/jcowgar or @jcowgar.