[Slightly OT] Secure file delete utility

I want to move to secure file deletes in my Rails app. My hosting
service has said they’d install Wipe for me (I mentioned it by name) but
I would very much like to use a utility that supports an asynchronous
mode so it doesn’t have a visible impact on the user experience. Does
anyone have any experience / advice on doing secure file deletes within
a Rails app they’d be willing to share?

Thanks,
Bill