[Cloud computing](https://en.wikipedia.org/wiki/Cloud_computing) is the on-demand availability of computer system resources, especially data storage (cloud storage) and computing power, without direct active management by the user.
- [Adagios](http://adagios.org/) - Web based Nagios interface for configuration and monitoring (replacement to the standard interface), and a REST interface. ([Source Code](https://github.com/opinkerfi/adagios)) `AGPL-3.0``Docker/Python`
- [Bloonix](https://bloonix-monitoring.org/) - Bloonix is a monitoring solution that helps businesses to ensure high availability and performance. ([Source Code](https://github.com/bloonix)) `GPL-3.0``Perl`
- [Bosun](http://bosun.org/) - Monitoring and alerting system by Stack Exchange ([Source Code](https://github.com/bosun-monitor/bosun)) `MIT``Go`
- [Cabot](http://cabotapp.com/) - Monitoring and alerts, similar to PagerDuty. ([Source Code](https://github.com/arachnys/cabot)) `MIT``Python`