Documentation
Checkers

Checkers

Checkers are the core building blocks of Update-Watcher. Each checker knows how to query a specific package manager or platform for available updates, parse the results, and report them in a consistent format. Checkers are read-only – they never install updates, pull images, or modify your system.

You can enable any combination of checkers in your configuration. The interactive setup wizard (update-watcher setup) auto-detects which package managers are installed on your system and offers to enable the corresponding checkers.

All Checkers

CheckerPlatformDescription
APTDebian, UbuntuSystem package updates via apt-get, with security-only filtering and phased rollout detection.
DNFFedora, RHEL, Rocky, AlmaLinuxSystem package updates via dnf, with automatic security update classification.
PacmanArch Linux, ManjaroSystem package updates via pacman.
ZypperopenSUSE, SLESSystem package updates and security patches via zypper.
APKAlpine LinuxSystem package updates via apk, ideal for Alpine containers.
macOSmacOSNative macOS software updates via softwareupdate.
HomebrewmacOS, LinuxOutdated Homebrew formulae and casks.
npmLinux, macOSOutdated globally installed npm packages.
SnapUbuntu, LinuxSnap package updates via snap refresh --list.
FlatpakLinuxFlatpak application updates across all configured remotes.
DockerLinux, macOSDetect newer Docker images for running containers without pulling anything.
WordPressLinux, macOSWordPress core, plugin, and theme updates across multiple sites and 11 environments.
Web ProjectLinux, macOSOutdated packages and security audits for npm, yarn, pnpm, and Composer projects.
DistroLinuxNew distribution release notifications for Ubuntu, Debian, and Fedora.
OpenClawLinux, macOSOpenClaw application update notifications with configurable channels.

Categories

System Package Managers

The primary use case for Update-Watcher. These checkers monitor the native package manager on your Linux distribution and report available system-level updates.

  • APT – Debian and Ubuntu
  • DNF – Fedora, RHEL, Rocky Linux, AlmaLinux
  • Pacman – Arch Linux, Manjaro
  • Zypper – openSUSE, SLES
  • APK – Alpine Linux

macOS

Monitor updates on macOS workstations and CI runners.

  • macOS – Native software updates via softwareupdate
  • Homebrew – Formulae and cask updates via brew
  • npm – Globally installed npm packages

Application Stores

Desktop Linux application stores that distribute sandboxed packages.

  • Snap – Canonical’s Snap store
  • Flatpak – Flatpak remotes (Flathub, etc.)

Containers

Monitor running Docker containers for image updates without pulling or modifying anything.

  • Docker – Image digest comparison for running containers

Web Applications

Monitor dependencies and CMS updates for web projects and WordPress sites.

  • WordPress – Core, plugin, and theme updates across 11 environments
  • Web Project – npm, yarn, pnpm, and Composer dependency updates with security audits

System

Broader system-level checks beyond individual packages.

  • Distro – New distribution release notifications (e.g., Ubuntu 24.04 LTS)
  • OpenClaw – OpenClaw application updates

Auto-Detection

When you run update-watcher setup, the wizard scans your system for installed package managers and offers to enable the corresponding checkers automatically. For example, on an Ubuntu server with Docker installed, the wizard will detect and offer to enable both APT and Docker checkers. You can always add or remove checkers later through the wizard or by editing the YAML configuration file directly.

Next Steps