Who is the best programmer of our time?

 Gennady Korotkevich

This guy has won Google’s programming contests for 6 years in a row now. At just 11 years old he was able to obtain a silver medal at International Olympiad in Informatics: a feat that even the best senior software developers and some Computer Science professors would not be able to accomplish. He then proceeded to to get gold medals in the following years, with three consecutive years achieving absolute first place. For more information of his feats check his Wiki page.

This guy is to programming, what Magnus Carlsen is to chess or Terence Tao is to Math. He outclassed even the best programmers at 11 years old, and for the past few years, no one was able to get close to his programming skill. Most of the time I would expect a person to be the best in his field for a year then the honor would go to another person the following year. This is the case for almost every other sciences (Math, Physics, etc…) not for this guy, who has consistently been ranked the number 1 programmer in the past decade.

Now despite his skill as a programmer, he may not be the most accomplished programmer. In fact he has not done much assides from competitive programming. Some other answers point to game developers or software founders that used their skill to create new and revolutionary software. However, these guys are not the best programmers, Gennady would beat any of them with his eyes closed, these guys are simply the most revolutionary and influential programmers, something which the question is not asking.