Like every year, after the second day of OpenFest there will be an after party, with lots of beer. It starts at 7:30 PM at Mixtape 5. There is free beer, but you need a blue bracelet from OpenFest 2015 in order to be granted access.
The “Bulgaria” hall is next to the Sofia’s City Garden, between the Sofia hotel and the Ministry of Defense. It’s close to the “Serdika” station of the metro. Map of the metro | Schedule