> and based on their own preconceptions of "programming at scale" as a pet project

Based on their experience working at Google. It wasn't just "preconceptions". (True, it also wasn't an examination of the field of the form that led to Algol and Ada, but it wasn't just preconceptions, either.)

>Based on their experience working at Google.

Yes, but that's their experience working at Google as 30+ years industry veterans and thought leaders (one would guess, mostly left to do their own thing, as prestige hires).

Not as regular developers doing everyday Google grunt-work...

Well, the founding myth of go says that it started from a conversation during a 45 minute C++ compile. I doubt that that was Rob Pike's personal "thing" project - he hadn't been there long enough to have a personal project that size. That was some big multi-person multi-year thing.

They had the limbo language in plan9, which has similar features and quirks. It seems most probable that the outcome of the 45 minute conversation wasn't "let's build a language from scratch", but rather "let's iterate on limbo".

You can get the details here,

"Creating the Go programming language featuring Rob Pike & Robert Griesemer"

https://changelog.com/gotime/100

There are other sources as well, this was just the one that quickest came to mind.

Actually it was, and they had a manager that covered up for them, allowing them to keep working on the project.

"Creating the Go programming language featuring Rob Pike & Robert Griesemer"

https://changelog.com/gotime/100

Had not been for him and Go would never gone beyond a prototype side project.

That isn't what I was claiming, though. I was claiming that the impetus for creating go was the issues raised by working with Google's regular code, not issues raised by working on Rob Pike's pet project at Google. Whether go became their pet project was outside the scope of my claim.

The only issue was waiting for builds and having to deal with C++ code, something that Pike shares the same opinion as Linus.