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containrrr/watchtower

★ 24,611GoAudience · vibe coderComplexity · 2/5MaintainedLicenseSetup · moderate

TLDR

Automatically updates your Docker containers to the latest images, stopping the old version and restarting with the new one while keeping your settings intact.

Mindmap

mindmap
  root((repo))
    What it does
      Auto-updates containers
      Checks image registries
      Graceful restarts
      Sends notifications
    How it works
      Monitors running containers
      Detects new images
      Stops old container
      Starts new container
    Use cases
      Home labs
      Media servers
      Local development
      Self-hosted apps
    Tech stack
      Go
      Docker
    Audience
      Self-hosters
      Home lab enthusiasts
      Developers

Things people build with this

USE CASE 1

Keep a home lab or media server running the latest software versions without manual updates.

USE CASE 2

Automatically restart self-hosted applications when new images are pushed to your registry.

USE CASE 3

Monitor multiple Docker containers and get notified whenever any of them are updated.

Tech stack

GoDocker

Getting it running

Difficulty · moderate Time to first run · 30min

Requires Docker daemon access and a running container to update; binary may need to be built from source or downloaded.

Use freely for any purpose including commercial. Keep the notice and disclose changes to the patent grant.

In plain English

Watchtower is a tool that automatically keeps your Docker containers up to date. Docker containers are self-contained software packages that bundle an application with everything it needs to run. When you deploy an app using Docker, it runs from a specific image, or snapshot. Watchtower monitors those running containers and checks if newer images are available in Docker Hub or your own private image registry. When an update is found, Watchtower gracefully stops the old container and restarts it using the new image, preserving all the original settings and configuration. It also supports sending notifications when updates happen, so you know what changed and when. This tool is best suited for home labs, media servers, and local development setups where you want your software to stay current without manual intervention. The maintainers explicitly advise against using it in commercial or production environments, where more robust orchestration tools like Kubernetes are the recommended approach. Note: as of the project's last update, Watchtower is no longer actively maintained. The tech stack is Go, and it runs as a Docker container itself.

Copy-paste prompts

Prompt 1
How do I set up Watchtower to automatically update my Docker containers on a schedule?
Prompt 2
Show me how to configure Watchtower to send me a notification every time it updates a container.
Prompt 3
What's the best way to use Watchtower with a private Docker registry instead of Docker Hub?
Prompt 4
How do I exclude certain containers from being auto-updated by Watchtower?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.