does that happen to all files or just that one?
ah "476 files, 326 compiled," suggests some are cached?
Nope, that difference is because some files are used in other build.
Yesterday I think I narrowed it down to the shadow-cljs timestamp, I was looking at https://github.com/thheller/shadow-cljs/blob/master/src/main/shadow/build/compiler.clj#L929-L1015 code
I'll let you know if I find the exact thing 🤔