[xudongz]

https://www.xudongz.com/blog/2020/ergoblue/firmware/ has a lot more information about the controller (with photos). In summary:

- The dongle is reasonably small. If you're traveling with it, you can toss it in your bag with a battery pack and it acts as a Bluetooth keyboard (for your phone/tablet/laptop/etc). You can plug it into your desktop, in which case it acts as a USB keyboard in addition to Bluetooth for other devices (phone/etc)

- Modifiers work fine but layers don't because some software still needs to maintain state. For example you might have the layer switch key on the left but want the next key to be on the new layer on the right. Theoretically one can do this with custom software on the computer though an external controller/dongle is straightforward and doesn't need to account for OS/platform differences. It also lets you connect to multiple devices simultaneous via Bluetooth.

- There's an option for hot swap switch sockets, in which assembly is putting the case together, soldering some header pins, and popping in the switches. There will be an assembly service for people who just don't want to do it but the process itself has been thoroughly optimized that it shouldn't be difficult.

[rendaw]

Oh thanks! I didn't realize the dongle attached to the computer, I thought it was like a power brick for the keyboard itself. That looks pretty nice!

So basically all the smarts so to speak are in the dongle, which you reprogram, etc?

[xudongz]

That is correct. Typically if want to update your keymap, you would just update the firmware running on the dongle. The firmware on the two wireless keyboard will pretty much never change.