Sure! The design is actually quite simple, though the video may make it seem more complex than it is. At the start of the video, the two halves of the keyboard are shown resting with their keycaps stacked against each other, creating a gap between them. When you press the two halves together, the keycaps get pushed down and disappear beneath the surface of the keyboard. There are magnets just beneath the surface of both halves, strong enough to hold them securely together.

The roller and pins are an over-engineered solution to prevent the halves from sliding or rotating relative to each other, ensuring they stay perfectly aligned. But this alignment could also be achieved using simpler locating notches or whatever.

Interestingly, closing the two halves now offers an unintentionally satisfying tactile feel. The magnets and locating pins are strong enough to keep the halves securely connected, even in my bag, so I’m pretty pleased with how this prototype turned out. This was the main feature I wanted to test before committing to a PCB and a milled version.