What makes it unusable outside the apple ecosystem imho is that while the C interop is amazing on paper, it sucks hard in practice due to the abomination of pointer types they build in.
The "all pointers are evil" attitude doesn't help when you want to use a C library and noone will write rewrite all these libraries.
Swift Caching Compiler - https://github.com/jrz/tools
The primary thing keeping me away from trying it again is I have to use Xcode instead of my beloved JetBrains IDEs where I know all the keyboard shortcuts.
Or am I going to have to vibe-code one.