The rkbrd3, shared by Andrew Rudenko aka prepor, is a low-profile parametric 34-key wireless split keyboard with – a case model featuring splay and optimized for wire wrapping.
Every hand is unique. The simple implication is that no keyboard fits all hands perfectly. A keyboard should either be mechanically customizable (see Svalboard) or tailored specifically to an individual's hand. With this keyboard, I'm sharing not only STL files for a ready-to-print version, but also a CAD model that can be customized via various parameters to achieve the most comfortable layout for your hand – prepor.
For instance, the author has relatively small fingers, so he uses a tight key spacing (17 mm). Others may find different spacing, concavity, and splay settings more comfortable.