I have created this board as I couldn't find a reliable module on the market that could fulfil all the requirements:

  •  HomeKit-enabled device
  • Mains AC supply 100-240 V
  • two relay channels
  • mains voltage switch input
  • small enough form factor to hide it behind a wall switch`

It uses Panasonic ADW1203HLW relays. These are resistant to arcing and work on 3.3V which is the main DC voltage for the onboard control electronics. Another advantage is that these are latching relays meaning it uses energy only to change a state - not to hold it.

It is designed in a way that it could be assembled as a single-channel device, thus saving a cost when 2 channel operation is not required.

More info and Documentation can be found on GitHub