ntfy/examples/ssh-login-alert/pam_sshd

# PAM config file snippet
#
# Put this snippet AT THE END of the file /etc/pam.d/sshd
# See https://geekthis.net/post/run-scripts-after-ssh-authentication/ for details.

# (lots of stuff here ...)

session optional pam_exec.so /usr/local/bin/ntfy-ssh-login.sh