How to interpret the nuance of "just so"?

Hello, all:

I am not sure how to interpret the nuance of “just so.” Do I detect a whiff of sarcasm in the examples below? Is it a feminine expression? What exactly does “just so” mean anyway?

  • Her house always has to be just so.
  • We take out a wall and Install a new window that lets the light shine just so on the dining room table.


“Just so” is often sarcastic, if someone is very meticulous and the speaker doesn’t like it.

However, “just so” can also be said with approval, if the speaker actually likes the precision.

“Just so” can also mean that something just is the way it is and that there’s no explanation for it, as in the famous “Just So Stories”.

Thank you very much, Jamie.