Also, they're saying: "At least half of our Tweepforce will be women". So they're suggesting that more than 50% of one gender is ok, as long as they're women.
Currently I think it's quite expensive (for locals). E.g. bedroom + living room costs > 3k PLN in Cracow, and probably more in Warsaw. At the same time junior dev can earn about 5-9k PLN net. My non-dev friends often are not even able to live in Cracow.