- [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](https://bosun.org/) - Monitoring and alerting system by Stack Exchange. ([Source Code](https://github.com/bosun-monitor/bosun)) `MIT``Go`
- [cadvisor](https://github.com/google/cadvisor) - Analyzes resource usage and performance characteristics of running containers. `Apache-2.0``Go`
- [checkmk](https://checkmk.com/) - Comprehensive solution for monitoring of applications, servers, and networks. ([Source Code](https://github.com/Checkmk/checkmk)) `GPL-2.0``Python/PHP`