I took the libnotify  binding for Squeak , adapted it to use the Pharo UFFI API and
enhanced it. It is available here  and seems to work well (see attached image).
It does not cover all libnotify possibilities (see the README on github) but it is already
usable to display notifications with eventually icons, set urgency, set timeout, etc…
It was great to try UFFI, it is really easy to use. Thanks a lot for it! 🙂