That's what I was doing as well (only in Bytom lol, to have even lower life expenses), till I retired at 41 years old. But, software engineers are an exception. Everybody else is pretty much making local salaries, which are lower than american ones in terms of purchasing power.
I lived like a king in Warsaw (renting a small apartment in the historical centre, eating out often) spending about 1/20th of my income.
These days I work for peanuts for my friend back from kindergarten and am enjoying it tremendously!