@JimB pointed me to the correct answer, this is a bug concerning with macOS spotlight indexing.
If anyone want's to track this, reported bug
using go's os like so:
and watching the destination folder using fsnotify
causes 2 events to fire,
can't seem to understand why
CHMOD is fired.
tried listening with python's watchdog shows 2 events as well, file creation and folder modification.
parent folder perms are
0777 file perms are