Cabot

Cabot is a stable and widely-used infrastructure monitoring platform, although it is not actively maintained. It is free, open-source, and self-hosted, offering features similar to PagerDuty, Server Density, Pingdom, and Nagios without their complexity and cost. Cabot provides a user-friendly web interface for monitoring services and sending alerts via various channels like telephone, SMS, or email without the need for coding.

It can utilize data from Graphite/statsd for generating alerts and supports alerting based on metrics, web endpoints, and Jenkins build statuses. Originally developed as a Christmas project at Arachnys, Cabot is written in Python and utilizes Django, Bootstrap, Font Awesome, and other technologies.