For ones who don't have enough time to read everything, our friends CTFNews wrote a small article about today's final: https://ctfnews.ru/news/415 (sorry, Russian version only)

All teams have already sent at least one flag! Congrats :)

Very soon we'll post some interesting information from our developers, but now some photos from final!

Today all teams got in usage those server stages, which consist of Orange Pi Zero. We learned from the developers why they chose this particular hardware.

-- The thing is the single board computers are popular, convenient for development (you can test your service anywhere, just put the computer in your pocket) and inexpensive. Besides they are cool and interesting to us :)
Another advantage: services are separated on a hardware level, which allows to avoid unexpected problems when through vulnerability of one service it's possible to steal flags from the others.