In my current job, I write production machine learning code often in Scala. I had never written a line of Scala before that, had no idea what the idioms were nor even what some of the inheritance and object privacy syntax meant.

I read through mountains of legacy Scala code while working on my first several projects, and have assisted dozens of other new developers (most of whom also have never once read or thought about Scala previously).

The assumptions people made in that codebase still give me nightmares, mostly over how foolish and lazy they are in little ways, little unexplained “self documented” things that create multi-hour stumbling blocks but which could have been written in a more “elementary” style in the first place (without sacrificing any necessary language features).

When I see things like, “any C programmer should know ...” I just slap my head in stupor. It just misses the point entirely. It’s of zero importance whatsoever to write code in language X in a style that benefits mostly only “people who know language X.”

Pretend you’re writing the code for a freshman intern who will look at it in 5 or 10 years with no prior knowledge of the language it’s written in, and now you’re in the correct ballpark for how to write professional software.