Cron Expression for Last Day of Month

import cron from 'node-cron';

cron.schedule('0 0 12 L * ?', () => {
  console.log('Running task...');
});

from apscheduler.schedulers.blocking import BlockingScheduler

sched = BlockingScheduler()
# Cron cannot express this cadence — use a rich trigger or interval instead.
sched.add_job(task, "interval", seconds=1)

This cadence is not expressible in standard cron; APScheduler's interval trigger is the idiomatic equivalent.

# GitHub Actions accepts 5-field UTC cron only and cannot express
# "0 0 12 L * ?". Approximate with a daily guard job and
# check the date condition inside the step:
on:
  schedule:
    - cron: '59 23 * * *'

GitHub Actions cannot express this schedule; the shown nightly job is the standard guard-job starting point.

# Unix crontab cannot express "0 0 12 L * ?".
# Common approximation — run near the window and guard in code:
59 23 28-31 * * /usr/local/bin/backup.sh >> /var/log/cron.log 2>&1

Standard crontab cannot express this schedule; the shown month-end guard is the conventional approximation.

import { Schedule } from 'aws-cdk-lib/aws-events';

new Schedule(this, 'Task', {
  schedule: Schedule.expression('cron(0 12 L * ? *)'),
});

Converted to the AWS EventBridge 6-field cron() syntax, which evaluates in UTC and requires '?' in one of the two day fields.