Cron Job

A scheduled task used to automatically execute scripts at specified times and dates.

A cron job is a time-based task scheduler found in Unix-like operating systems. It allows users to schedule scripts or commands to run automatically at specified intervals, such as every minute, hourly, daily, or on specific days of the week. The schedule is defined using cron syntax, a five-field format specifying minute, hour, day of month, month, and day of week.

Cron jobs are commonly used for maintenance tasks like log rotation, database backups, cache clearing, and sending periodic reports. In web development, they handle tasks such as refreshing API tokens, syncing data between services, and triggering batch processing jobs.

In serverless architectures, traditional cron jobs are replaced by scheduled triggers. Cloudflare Workers supports Cron Triggers that invoke a Worker on a defined schedule. Similarly, AWS offers EventBridge scheduled rules for Lambda functions. These scheduled invocations are useful for tasks like API health checks, data aggregation, and periodic cache invalidation.