Jenkins is a self-contained Java-based program, ready to run out-of-the-box, with packages for Windows, Mac OS X and other Unix-like operating systems.

Munin is a networked resource monitoring tool that can help analyze resource trends.

Icinga is an open source computer system and network monitoring application.

GKrellM (GNU Krell Monitors) is a system monitor software based on the GTK+ toolkit that creates a single process stack of system monitors.

Datadog is a monitoring service for cloud-scale applications, bringing together data from servers, databases, tools, and services to present a unified view of…

HappyApps is an online app uptime monitoring platform.

Buildbot is a software development continuous integration tool which automates the compile/test cycle required to validate changes to the project code base.

Monit is a free, open source process supervision tool for Unix and Linux.