are the circuit diagrams of Pyra available to the public? If so, where can I find them? Some git repo?
Which program is used for Pyras circuits and PCBs? KiCad? geda?
Not sure about the Pyra, but the Neo900 project uses(/used?) Eagle  for the PCB design.
Well Nikolaus (HNS) who designed the circuitry for the Pyra as well as the neo900, just posted prior saying it was done on eagle.Neo900 used it, but (fortunately) moved away from proprietary Eagle to free KiCad, according to
In my company, we used to use Eagle for smaller and medium size projects, but phased it out in favour of KiCad, too. For really big projects, we still depend on proprietary software, unfortunately: Altium Designer.