Custom GPS Hardware for use with NTP Stratum 1 servers, along with system configuration documentation.
The hardware designs for my specific device. There are many GPS options for building a Stratum 1 NTP server. This is just one take on it.
The firmware code and binaries for the device described in the Hardware section. Built in the Arduino IDE to be maximally approachable.
Configuration guides for setting up NTPd, NTPsec, or Chrony on Ubuntu, Debian, Alma, or Rocky to acquire the PPS signals provided by the GPS and use them to discipline the local clock and act as a Stratum 1 server.