Simple bash script that sends notifications X minutes before events saved in calcurse. Will also send notifications X minutes before midnight for daily events. In addition, it has an explicit line for initiating vibration/sound with feedbackd on devices that support that.
Simply add something like the following to your crontab to enable. This line will notify you about events 30 minutes before they happen by running this script every two minutes.
*/2 * * * * export DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/$(id -u)/bus; /path/to/calendar_appointment_notify.sh 30 2
Dependencies:
libnotify
calcurse
bc (shell calculator) and date, which should be present on almost every UNIX-like system
optionally feedbackd