On the flip side, the code that he originally wrote would never scale to a billion dollars. It was wildly inefficient. Someone with a bit more experience as a game developer, someone a bit senior if you will, was necessary to turn the idea into what it is today.

> It was wildly inefficient.

Spoiler: Minecraft Java Edition is still wildly inefficient despite having a trillion dollar company backing it for 10 years.

Wildly? I'm sure the code might be inefficient in many ways, but there have (as I understand) been performance improvements such as in chunk loading and map generation.

Even the latest (apparently controversial) recent redstone update is meant to take account of performance - https://www.minecraft.net/en-us/article/minecraft-snapshot-2...

"The performance impact of Redstone wire (connected blocks of Redstone Dust) has been improved"

I've no idea how true that statement is, of course!

> performance improvements such as in chunk loading and map generation

True but the general game loop is still (wildly) inefficient; hence the multitude of performance mods (Sodium, Lithium, FerriteCore, ImmediatelyFast, etc.) that are considered basic mods for anyone wanting to play the game without dipping down to tragic fps.

All of that functionality could (and should!) have been folded into the Minecraft source years ago. But Microsoft didn't buy Minecraft to give people a good experience - they bought it because it generates a non-trivial amount of money from things like Bedrock IAPs, merch licensing, etc. Updating the games is just a necessary evil that keeps the money flowing.

(Bedrock, on the other hand, is much more optimised because, IIRC, the core game was written in C++ targeting mobile devices and needed to be efficient to even work.)

Who? They only did have a handful of people when they sold for $1 billion. Were any senior devs?

I think it would be fair to call Jens the Principal Engineer on Minecraft. Is that senior enough?

I generally agree, but I think it's more subtle than that. Levels and titles aren't really about productivity per se either, they're about defining role expectations and conferring authority to ICs in a corporate environment where there are hundreds or thousands of developers, and they are inextricably linked to the communication needs that dominate productivity in large organizations. They often don't even map between departments, let alone different companies, and especially at smaller companies that don't have the headcount for any meaningful calibration to exist.

From that lens, Notch's "level" when he created Minecraft is pretty much undefined. He obviously had technical and entrepreneurial skill, which gave him huge credibility, and is a fast-track to a certain title / level at acquisition time, but that says very little about his ability to meet the expectations of a Microsoft engineer that worked their way up to that level through promotions.