But the keys in the middle are differently sized; there are two of them for the three rows of keys. You can reprogram, but you can't just add a regular "Y" key on the left and a "T" key on the right that are where they are supposed to be.
The hardware is open; you can build or modify the keys as you please. There a number of variants with different key layouts: https://deskthority.net/wiki/ErgoDox
