@menherahair :redeyeorb: @ @△ TRiANG-ouL's avatar ▽ yea.
its called from root using run-parts which just executes scripts in a dir.
the actual crontab looks like this. this is the default root crontab on alpine.
# do daily/weekly/monthly maintenance
# min hour day month weekday command
*/15 * * * * run-parts /etc/periodic/15min
0 * * * * run-parts /etc/periodic/hourly
0 2 * * * run-parts /etc/periodic/daily
0 3 * * 6 run-parts /etc/periodic/weekly
0 5 1 * * run-parts /etc/periodic/monthly