Extended version with wrist pads can be found here: Charybdis/readme.md at main · Bastardkb/Charybdis (github.com)
I find a standard 30-degree stand is pretty aggressive, but flat also not working for me as well. This might be helpful to try different angles to see what works for you.
The top plate is remix of this: https://github.com/Bastardkb/Charybdis/blob/main/files/4x6/tent_alien_30deg_v125.stl
Needed hardware (4 of each below per side):
Printing:
Only the top plate is not symmetric, mirror it for another side.
Update: added case bottom plates with hinges. Print them vertically with some supports.
The author hasn't provided the model origin yet.