Hi @basie, it shouldn't matter, as long as you wire it into the microcontroller correctly, and you reflect that in the firmware, is at least how I've understood it.
I hope the following quote helps:
"There are two options for soldering the diodes, all heading towards the
switch or all heading away from the switch. These two ways are called
“row-driven” or “column-driven” and here again it is cruciual for the
firmware and the actual wiring to be on the same page. ... I went for the
“row-driven” setup (visible by the direction of the diodes, the black line
being towards the key-switches). "
src:
https://github.com/adereth/dactyl-keyboard/tree/master/guidePlease post images of your build, and share your experience.