[100011_100001]

I have to share my story, because I read the comments here and the post and I fell into a similar trap about a year ago.

It all sounds good. Compact keyboard has always appealed to me, so did ergonomics, I bought a split keyboard (36 keys) with Miryoku layout and went to town. I lasted about 1 month and quit.

What happens is the amount of keys you have to type concurrently increases forcing your fingers in weird positions.

For example, typing the following 48 characters

   if (needle in [a, b, c]) {
      println('found it')
   }

In a standard keyboard you have to press 53 key presses (parenthesis is Shift+9 so that's two keys for a single parenthesis etc)

In a Miroyoku layout it's 59 key presses. This might not sound like a lot but it's a ~10% increase.

It also doesn't account for a very big problem, arrow key navigation for non VIM users. Since pressing the arrow keys requires two button presses in smaller keyboards, and done repetitively it's a huge slow down in navigating text. Now there are solution to this, most IDEs can support VIM keybinds, or have their own hot keys to skip words etc. To me the arrow key navigation is what got to me long term and I opt4ed out of it.

[guidoism]

I'm at 48 keys right now, but I would like to counter that it's not just key presses you should care about, but also movement of the hands. My setup definitely isn't perfect but your example is exactly the kind of key sequence I have optimized for. Having parenthesis and the various brackets on the home row or very close is super awesome for programming.

Honestly, you don't need to go down to so few keys, just program your keyboard to have one more layer that puts those special characters into a better place for you and I think you'll get 90% of the benefit of the OP's keyboard.

[ZeroGravitas]

What actually tipped me over to doing this 'layers' thing, was exactly these keys being in different places on different keyboards.

Having (){}[]-+ in the same place and easily touch-typable was much better than having them in different places depending on what I was typing on (dvorak already has < and >, ' and " period and comma in a sensible place).

[guidoism]

Exactly! I can hold the layer key and do the entire ()[] sequence for links in markdown in one go and every time I do that it makes me smile.

[chrisBob]

It is interesting that you think arrow keys are a likely blocker. I have a Kinesis Freestyle Pro and my favorite feature is having the arrow keys on the second layer as vim style HJKL. I also have backspace, esc and del on the second layer with the right half of the space bar as the layer shift key. Moving these common keys made a huge difference to me, and was an easy transition since I exercise them so much.

The reason I couldn't move to a much smaller keyboard is that the less common keys that I use a few times a day like `{}\<>? feel like they would be so much harder to retrain. Similarly I am only passable at touch typing my number row, and I don't think I could survive without the labels for the symbols that are usually over the numbers.