How many times can one person perform a miracle?

It's not a miracle, this programmer was just smart enough to see something that nobody at Rockstar had seen. Or nobody in the engineering org cared to look. These could both be good reasons for somebody higher up to hire a "star consultant", no?

> It's not a miracle, this programmer was just smart enough to see something that nobody at Rockstar had seen. Or nobody in the engineering org cared to look.

Or more likely, no one had time to look. I keep see people acting like not fixing something is because the devs don't care. More often than not it's because we're being told to do something else instead.

Sure, I'm not saying the Rockstar devs are stupid. I was addressing the idea that it was some kind miracle that happened here, rather than just competent engineering.

"I don't have time to do it myself" is probably a very common reason why consultants are hired.

Do you honestly believe that the person can look around any code base and find significant speed increases? Do you think he can significantly increase the speed of Firefox, or Excel, or SQLite? Maybe he is the solution to Mozilla's woes—just hire him for a month, he will increase Firefox's speed by 70%, and everyone flocks from Chrome to Firefox for the increased speed. At least, until next month that Google hires him and he increases the speed of Chrome and everyone flocks back. With such a valuable resource, it is unethical to monopolize—there should be a waitlist so every company can use his genius. By the decade's end, every piece of software will be running more than twice as fast.

Or maybe this was a case of a rare low-hanging fruit lying around for someone to find. Maybe the entire software industry is not one giant low hanging fruit waiting for the right genius to emerge and pick.

I don't see how you think that's what the parent commenter is believing. For starters, the modder didn't make "GTA V 70% faster", he made one small (but noticeable) part 70% better.

And yes, there are many code bases where performance isn't prioritized in all areas, and one totally can expect a skilled engineer coming in to look at performance to find nice speed increases here and there. Not because they are magically better than everyone else, but because a) they are given the freedom to spend time on it where nobody else has been and b) because they are possibly more familiar with approaches and tooling than a dev that hasn't had the opportunity to prioritize performance. All your examples likely do have such people available, and thus bringing someone in is less likely to find something really juicy, unless they have some blindspot. Large game projects for sure have performance experts, but maybe they primarily spend their time on in-game performance and initial resource loading was a blind spot. Maybe that's a common blind spot. And outside games that's commonly waaay worse - performance isn't prioritized, and to be fair the fact that slower-than-necessary software usually sells just as well makes that understandable economically for a long time. But also makes it difficult if it gets to the point where it should/must matter.

> Do you honestly believe that the person can look around any code base and find significant speed increases?

In my experience, YES! It is often the new set of eyes (especially if they are on a a smart head with lots of time, energy and will available) that finds new solutions, optimizations and bugs we never thought about. And the people I work with are the smartest people I have ever met and that still is nowhere near enough to ensure that the large scale software projects we work on have had all the possible large optimizations done already.

Yeah, the answer in this case is that there was some low hanging fruit he was able to find. There's not always a simple solution to latency and performance problems.