It’s really just an ATTiny85 – a favorite of ... and [Micah] created a board that fit his needs perfectly. Four of the six IO pins on the ‘Tiny85 are broken out on a pin header; two are ...
Enabling internal pullup resistors in the ATtiny85 not only takes care of proper biasing of the comparator pins, but also helps ... you could just order out some boards from OSHpark.