"10x engineers" do exist but generally-speaking it's not worth the effort to pursue them because to do so means you're taking your eye off the real concern: building a 10x team. I can tell you from personal experience and the anecdotes of several of my colleagues that a group of 10x engineers do not make a 10x team. Often quite the opposite. Remember, it's teams that deliver software, it's teams your company is depending on. Focus on making 10x teams.