dockcheck

As a single Bash script, it integrates easily into cron jobs or shell aliases, with no external dependencies beyond Docker, jq, and regctl, making deployment straightforward.

Supports multiple channels like Discord, Telegram, and SMTP via configurable templates, with snooze features to avoid duplicate alerts, as detailed in the README's notification section.

Automatically backs up previous images before updates for rollback, with configurable retention periods, providing a safety net against breaking changes, as explained in the Image Backups section.

Uses xargs for parallel update checks, speeding up scans across many containers, with tested limits up to 32+ subprocesses, reducing wait times in large environments.