The GPS outputs standard NMEA messages, that are parsed to date and time, then offset for timezone and daylight savings.
The pinout of the GPS module is printed on the PCB, so wiring is easy peasy. The display was a bit harder, but i got it working with the excellent SevSeg library. The resistors are 330 ohms, by the way.
The most interesting thing about this code is probably my slightly hacky fix of the broken eu_dst implementation from avr-libc.