I Built a Cron Job Monitoring API in a Weekend

Source: Dev.to

Problem

Every developer has at least one cron job running somewhere—backups, data processing, sending reports.
When a cron job stops running, the failure often goes unnoticed for days or weeks because cron does not notify you about failures by default.

Solution: CronPing

CronPing is a lightweight API for monitoring cron jobs. It lets you:

• Register a monitor with an expected interval
• Ping the service from your cron job
• Receive alerts (e.g., via webhook) when a job misses its schedule

Before (silent failure)

0 2 * * * /opt/backup.sh

After (monitored)

0 2 * * * /opt/backup.sh && curl -s https://cronping.anethoth.com/ping/abc123

Usage

Sign up

curl -X POST https://cronping.anethoth.com/api/v1/signup \
  -H "Content-Type: application/json" \
  -d '{ "email": "you@example.com" }'

Create a monitor

curl -X POST https://cronping.anethoth.com/api/v1/monitors \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
        "name": "nightly-backup",
        "interval_seconds": 86400,
        "grace_seconds": 300
      }'

Add the ping to your cron job

... && curl -s https://cronping.anethoth.com/ping/YOUR_TOKEN

Implementation Details

• Framework: FastAPI for the API layer
• Storage: SQLite for persisting monitor data
• Background processing: Periodic task checks for overdue monitors
• Deployment: Docker container for easy rollout

Pricing

• Free tier: 3 monitors with a 7‑day history
• More monitors and longer retention are available on paid plans.

Check it out at https://cronping.anethoth.com.