We (exco, kist, makefu and me) try to create a modular opensource nixie clock The clock is based on a atmega32u4 esp8266 , there will be optional i²c rtc chip for good time accuray.

There will be three types of Modules

• HV Supply Module (contains max1771 stepup for generating Tube supply voltage)
• Controller Module (contains ESP8266 and RTC)
• Nixie Module (Contains 2 Nixies and two Attiny2313 i²c slaves)

maybe you find some additional information here https://wiki.euer.krebsco.de/samu.html#nixie https://excogitation.de/wiki/#IN-12A%20nixie%20clock