Diun

Diun (Docker Image Update Notifier) is a CLI service that watches container images on Docker/OCI registries and alerts you when an image is updated. It runs as a single Go binary or as a container and supports multiple environments for discovering what to monitor.

Key Features

• Watches repositories and reports new tags and image updates
• Include/exclude tag filters using regular expressions
• Built-in cron-style scheduling and concurrent worker pool for parallel checks
• Multiple providers for discovering images to watch (Docker, Kubernetes, Swarm, Nomad, Dockerfile, file)
• Notification outputs to services such as Gotify, email, Slack, Telegram, and others
• Healthchecks support to monitor the watcher process
• Enhanced logging for auditing and troubleshooting

Use Cases

• Get alerts when base images or critical dependencies publish new versions
• Monitor Kubernetes or Swarm workloads for upstream image changes
• Track specific tag patterns (for example, only stable releases) and notify ops channels

Diun is a practical building block for container operations, helping teams detect upstream image changes quickly and integrate notifications into existing workflows. It is lightweight to deploy and works well across heterogeneous platforms and architectures.