I would describe myself full stack under that definition. Most "full stack" people I know that sit in my Uni courses have mostly learned Java EE + Oracle DB or Javascript + /dev/null^w^w MongoDB. Most of them would probably not be able to construct a relational database or libc from scratch.

Granted, such knowledge isn't immediately useful since it's something I or anyone is likely to do but it grants insight into systems. I know roughly how a query optimizer does and what it can, and more importantly, can't do.

When you know a system you can optimize for it. When you don't know a system you can only follow someone else's advice on how to optimize for it.

> /dev/null^w^w MongoDB

Nitpick: That's actually either three ^w or just one ^w, depending on how your WORDCHARS is set up. :)

I'm sadly not that much of a Vim expert, Hackernews lacks formatting for a strikethrough and I wasn't sure how a ~~/dev/null~~ would be interpreted.

How much quantum mechanics do you really need to know to code the next Uber for hamsters?

Isn't the current quest in quantum mechanics (to find a grand unified theory) to find an abstraction that does leak? At the moment it's too self contained and doesn't explain anything about the macroscopic world.

In any case, having a basic understanding of the next level up (the electron) has proved quite useful to my career, otherwise I wouldn't know how turning things off then on again affects the machines I'm working with.