git clone git@github.com:pmateusz/quake.git
mkdir build && cd build
cmake ..
make --jobs 4

Astronomical data about sunrise and sunset were downloaded from Her Majesty's Nautical Almanac Office.

1. During build make asks for username and password to a GitHub account

   Ensure SSH Agent is running. The following command should print one process called ssh-agent.

   pmateusz@debian:~/dev/quake/build$ ps -p $SSH_AGENT_PID 
    PID TTY          TIME CMD
    788 ?        00:00:00 ssh-agent