A cute systemd feature to get the system clock roughly correct: if the system time is before the compilation time of the systemd binary, it moves the clock forward to that time!
I'm surprised there aren't more interpreted languages with a first party type checker.
Python has several good type checkers, Ruby has Sorbet, and there are others.
Having zero compilation time *and* a full IDE seems like such a compelling design, at least on paper.
I've been compilation buffers in Emacs recently and I really appreciate the error and warning counts shown in the modeline.
I've added the equivalent feature to deadgrep: it shows result counts! Really useful when you're doing big refactorings.