crontab

Classic cron on Linux and in containers.

The most common case: the crontab line already exists, it just needs to report.

Before

0 3 * * * /usr/local/bin/backup.sh

After

0 3 * * * /usr/local/bin/backup.sh && curl -fsS -m 10 --retry 3 https://ping.tickwatch.dev/YOUR-KEY > /dev/null

Things to watch

A percent sign has special meaning in crontab — escape it as \%, or the line is cut short right there.
The monitor schedule must match the crontab schedule. A mismatch produces false alarms.
The monitor timezone is the timezone of the server running cron, not your own.
cron has a minimal PATH: use absolute paths to binaries, curl included.
If cron runs inside a container, curl may be missing — add it to the image or use wget.

Without curl

wget -q -T 10 -t 3 -O /dev/null https://ping.tickwatch.dev/YOUR-KEY