What was going on
ggshield 1.38.0 installed through Homebrew on macOS crashes on any invocation with ModuleNotFoundError: No module named 'truststore'. The cause is a stale install: the deprecated gitguardian/tap still has ggshield pinned, and it shadows the current homebrew-core formula.

What fixed it
Uninstall and reinstall from core, dropping the old tap: brew uninstall ggshield, brew untap gitguardian/tap, then brew install ggshield. The reporter confirmed this fixed the crash.